In Hal, Hal is a robot who has been programmed with the personality of the real Hal, to help his former lover deal with the devastating loss the real Hal's death was to her. A blow to the head Hal receives later snaps the truth of the matter to him, that he is in fact a man who was driven insane and believed himself to be a robot after the death of his lover and the girl he has been helping get over her loss? A robot programmed with the personality of the dead girl to help him deal with his loss.
In the Anime/Manga/Novel Another, the only way for the dead classmate to be found is for them to be killed, as even they don't know their true identity. They do, however, have an ace up their sleeve, as Mei Misaki can use her doll's eye to see "the color of death." It is in this way that they find the dead classmate was in fact not one at all, but the protagonist's aunt and classroom teaching assistant. Their being the same person is not an example of this trope, however: it's only a surprise to the viewer. The fact that she was dead? No one saw that coming, not even her.
The Big O, to the point of main character Roger Smith actually crying out "I'm one of the tomatoes!" Yeah, it sounded dumb, but it was a shocking twist. But it gets weirder still near the end, when he discovers this may not be the case, and he may have existed before Paradigm...
Big Bad Alex Rosewater also goes through this when he realizes that he was just another one of Gordon Rosewater's "tomatoes".
Combattler V: The Dragon Garuda discovers, to his dismay, that he is actually the latest of a series of identical androids.
In D.Gray-Man, it's eventually revealed that Allen is actually the host for the Fourteenth Noah, which is how he can control the Ark. Unfortunately for him, he woke it up, and now the Fourteenth is trying to take over his body.
The second season has one regarding secondary protagonist Suou Pavlichenko. Her mother says she's a clone of the original Suou, who died eight years before. Turns out, as her father explains, she's an Opposite-Sex Clone of her brother Shion that he created with his contractor powers. Shion used himself as a reference since the original Suou was his twin and gave her Fake Memories to fill in the gaps. Least to say, Suou was not pleased when she found out.
Mazinger Z: Secondary character Erika was an amnesiac girl who barely remembered her name. She felt an odd, devastating inner emptiness, but in spite of it she thought she was a normal girl. And then The Dragon Baron Ashura appeared and revealed that in reality she was a human-looking robot built to murder Kouji Kabuto. She freaked out considerably -and understandably-, and she refused believing it.
Lorelei thought she was an average, little girl with a slightly eccentric and weird father. And then she found out that she was in reality a Robot Girl, and the key component to start a Humongous Mecha.
Maria Grace from UFO Robo Grendizer believed she was an average girl... until her gradnfather revealed that she was an alien.
And her brother Duke Fleed played this trope in the Gosaku Ota manga continuity. Dr. Umon had wiped out his memories so they did not torture him and he was able living like a normal human being. However, when a stream of reports of ufo sightings started to arriving to the Space Research Laboratory he started to feel odder and uneasier, although he did not udnerstand why. It was when the Vegans started to strike nearby cities he finally remembered he was an alien.
In Serial Experiments Lain when the eponymous character realizes in what is one perhaps the most dramatic and mind-bending reveal in a seriesful of dramatic and mind bending conspiracies that she is in fact a program engineered to be the god of the new world created when the internet/Wired overtakes reality.
In Dragon Ball Z, he finds out from his long-lost brother Raditz at the beginning that he is an alien (Saiyan) sent to kill all humans on Earth. He forgot his purpose and mellowed out after he fell off a cliff and hit his head as a child. It takes the death of Vegeta at the hands of Frieza to finally come to terms with his origins, resulting in his "I am the Super Saiyan Son Goku speech."
There's also a sort of in-universe example of this. Goku's friends have all known since soon after they met him that he once transformed into a giant ape monster and killed his own adopted father, but they keep it a secret from him. Goku eventually has his Tomato in the Mirror moment much later, but it's already been spoiled for the audience.
In Ergo Proxy, Vincent Law is the Ergo Proxy of the title, and it initially acts as a separate part of him without him knowing it. He previously erased his memories so that he could live a normal life as a human.
This show gets a second one: Re-L is a clone of the Monad Proxy. She discovers this when she returns to Romdeau and finds a replacement clone has been created.
In Star Driver, Marino, Mizuno's older sister, is a clone created by Mizuno's first phase ability so Mizuno wouldn't be lonely.
In Fullmetal Alchemist, Number 66, formerly Barry the Chopper, causes Alphonse to doubt that he ever was human. This, coupled with his lack of memories regarding certain events about his childhood - well, you do the math. Turns out not to be the case; the reason for Al's memory gaps is simply that he was a little kid, and logically wouldn't remember a lot of things from when he was so young.
Also, The sigil that binds the soul to the armor-body was a little faded. Ed made a point about fixing it up later on.
Plus, all bodies and souls not belonging to each other will eventually begin to reject each other. Though what "reject" means exactly is never explained, it could be reasonably assumed that memory gaps would be a possible effect.
And a Bilingual Bonus: his name "Al" is pronounced "Aru" in Japanese, which is identical to the verb 'aru', which means "to exist" as an inanimate object — 'iru' is for living things that exist...
In Gantz, this is what happens with Kishimoto. Apparently, she actually failed suicide, and the her that was sent to Gantz was actually a clone. When she gets sent back to the normal world, she sees that the other her is living normally at home, and she has no place to go.
Gate KeepersOne of their teachers was an Invader, and he didn't know it. Dealing with him really didn't sit too well with Megumi, who had been a reluctant member of the team to begin with, and it may have been among the reasons for her Face-Heel Turn later on.
Double-Subverted in Gravion: Leele discovers that she's apparently one of the Zeravire that's been attacking the Earth. In the episode afterwards, it's Hand Waveed that her memories were mixed up from contact with one of the Zeravire. But as it turns out, she is a Zeravire. Sort of. She is in fact the niece of the alien scientist who created them, and shares the surname Zeravire.
Gundam 00: Anew Returner is an Innovator whose memories of her true identity were wiped out so she could become Ribbons's Manchurian Agent.
Desty Nova learnt the same thing about himself at some point before his introduction. It is not known if the truth drove him insane, or if his insanity helped him deal with the truth. Seeing as he was the only person who doesn't seem to care about their shared condition, it was likely the latter.
Much later on,in the sequel manga Last Order, Alita gets her own TITM - twice. The first is when she learns that her past self, before her amnesia, was directly responsible for a catastrophe that resulted in the death of millions and the transformation of the entire Solar System into a Crapsack World. The second is when her brain, her last remaining piece of humanity,is revealed to have been removed at the start of the series and placed in a box she's been unknowingly carrying about for the past three volumes. She's told this just as it's exchanged for her friend's,resulting in a literal breakdown of her nanomachine body.
Taikoubou from the Houshin Engi manga later finds out that he's actually the other half of Ou Eki, and when they combine, they form one of the "First People", Fukk.i
Kiddy Grade: One set of Éclair and Lumières has a slightly subverted version of this, as they realize something is not quite right first, before realizing they were clones and breaking free of Alv's Mind Control.
This also happens in the Reverse manga when Éclair and Lumière that the readers are reading about turned out to be fakes that Alv and Dvergr made as a test (tying in to the aforementioned event in the anime).
In King of Thorn, one of the protagonists turns out to be a tomato in the mirror. Kasumi is actually a Replacement Goldfish Medusa construct created by Shizuku after the real Kasumi died.
One episode of Paranoia Agent follows three people who meet in an online chat room and decide to make a suicide pact together. Throughout the episode, they attempt time and time again to kill themselves, and fail every time. In the end of the episode, one of them realizes that their first suicide attempt was, in fact, successful—for the rest of the episode they've been ghosts, and none of their attempts have worked because you CAN'T kill yourself if you're already dead. It also explains why Lil' Slugger/Shounen Bat freaked out at their presence—he only targets the living.
RahXephon is riddled with examples (along with Luke, I Am Your Father revelations). Not only is Ayato himself a half-human, half-Mulian, but no fewer than two other characters discover the shocking truth about their own origins along the way; one of them was previously mind-wiped to make her forget them.
Shakugan no Shana gets this out of the way with Yuji in the first episode — as Shana bluntly explains to him, the real Sakai Yuji was erased from reality and eaten by a Rinne. All that he is is a temporary placeholder, meant to ease the strain on existence caused by the erasing of the original, and once his power of existence runs out, he'll cease to exist as well and reality will arrange itself so that Sakai Yuji will never have existed in the first place.
Sola has a Wham Episode where Yorito realizes that he's a clone made of paper, as a replacement for the original who died centuries before, by his paper-manipulating sister.
Sorcerer Stabber Orphen: Esperanza Reika thought her little sister Lycoris was dead and had been revived by her Creepy Child boss, Escalenna. It turns out Esperanza was the one who has truly died.
Played with in xxxHOLiC when Yuuko reveals that Watanuki is a clone of Syaoran... of sorts. Specifically, his birth was generated to replace the real Syaoran's place in the universe when Syaoran was removed from his timeline.
This is the entire premise of Zegapain. Kyo believes that he is playing a video game in which he pilots a giant robot fighting against aliens trying to wipe out the computers that hold the brain patterns of the remnants of humanity, only to discover the "game" is the real world, and he is merely data in one of those computers.
Kitsune To Atori - One of three stories that have absolutely no relation to each other whatsoever. The plot of the first chapter was pretty confusing but involves a tale of two sisters. The younger sister, Atori, hates lies and sees the foxes (who have magical abilities and can transform into other forms) as deceitful and evil, which is also partly fueled by the fact that her older sister suffered a fox attack and now bears a scar on her eye, which she covers at all times. Thinking that her sister is being too lenient on the foxes, she becomes confused when she reassures her that "It's fine if you're not honest, as long as you stay by my side." Later Atori finds her older sister removing their sword that cuts through spells and attacks her, assuming her to be a fox disguised as her sister. Through a series of revelations it's revealed that she and her sister had been lying all along. Atori is actually a fox and her "sister" used a spell to make her forget her painful past and live peacefully.
The third chapter of the manhwa, and the last one-third part anime movie of Shin Angyo Onshi invokes this. A young fisherman found Munsu and tells him that a miracle-doing physician in his island village is experimenting the dead. Munsu and Sando investigates the matter, and found out that said physician is indeed experimenting the dead. The twist came when Munsu tells the young fisherman to kill her beloved sister, which he tearfully done... the illusion came crashing down, and it turns out that the physician zombified the population of the whole village, who died when a plague swept over the area, and covered it with mandrake-induced illusion. Said young fisherman finally realized that he is not the sole survivor, but a zombie like everyone else and promptly killed himself.
It is speculated that this trope applies to Munsu's Sando (Chun Hyang) as well. Many stronger Sando are animals/magical beasts that can take human form, as most clearly demonstrated by Hwang's Sando, who first can be seen as a giant wolf/bird hybrid beast but later presents herself as a little girl. The cute ChunHyang was known as Mong Ryong's constant companion, and Mong Ryong himself is known as a veterinarian. It is not a far stretch to speculate that Chun Hyang is the same.
A stand-alone ero-manga titled Borderline uses this: a man falls in love with a mannequin, which then comes to life and makes love with him. It later turns out that they were both mannequins to begin with.
In the first episode of Mnemosyne, Kouki Maeno discovers that he's actually a clone of the original Kouki Maeno. Unusually, he actually takes it pretty well: after one Attempted Suicide, he settles down and grows into a well-adjusted man.
Cardcaptor Sakura hosts the second type: at the end of the first arc, the series takes an abrupt twist when the cast (and audience) learns that Yukito wasn't human. Needless to say, the character in question goes through several of the same angst and questioning of their own existence as is described above when they later find out themselves.
There's also Elliot turning out to be the core illegal contractor of Humpty Dumpty and while not the Headhunter, ended up being the one to kill half of his family under HD's control.
Gilbert turning out to be a Baskerville also counts.
In After School Nightmare, the main character is invited to take a secret class at their boarding school necessary to graduate in which students face their biggest fears and personal issues, fight each other, and seek the keys to unlock a giant set of doors. One assumes this is merely the school's complicated therapy for a group of very, very troubled kids, but in the end it's revealed that they're all unborn children, and "graduating" is actually being born. While the main character appears to be struggling with their gender identity, they're actually making the choice of which of two opposite-sex twins will live. It's unclear what this implies for the other students; Kureha was supposedly raped as a child, and Sou was involved in an incestuous relationship with his sister, but all that happened before birth. The questions this raises can result in some Fridge Horror.
Mochi, Suezo, Golem, Tiger and Hare in Monster Rancher turn out to be the Phoenix whose soul was split into five pieces.
A version occurs in Death Note when Light loses his memory of being Kira, spends several episodes working with the investigation to uncover Kira while vowing to bring him to justice, and finally recovers his lost Death Note, at which point he realizes that he is indeed a mass-murderer with a god complex, and his memory loss was part of his own Batman Gambit.
Hyouka Kazakiri thought she was a normal girl until flying debris breaks her head open (the injury heals up) to reveal that she is really an artificial angel, an aggregation of Academy City's AIM (psychic energy) fields. She doesn't take it well, until Touma assures her that he and Index don't care that she's not human; she's still their friend.
Arisa Meigo thought she was a normal girl. Toward the end of the Miracle of Endymion movie, everybody learns that she is really a part of Shutaura Sequenzia that separated from her. Even Shutaura didn't know about this at first.
In Yu-Gi-Oh! ZEXAL, Shark slowly realizes that he is a Barian, even smashing his mirror when he experiences his past-life memories and recognizes the pendant around his neck.
Screaming Lessons (imagine The Outer Limits as a shoujo manga + horror- almost any happy endings): In "The Boyfriend Story" a girl uses a cell phone app to create the perfect boyfriend, who overloads when she adds too many features. The cell phone apps can make girls and friends too, as well as bosses, idols, cops, spouses, children...
One Black Jack chapter involved a young boy in a hospital who notices that the doctor, nurses and even his mother have changed personalities, and decides that aliens must have taken over their bodies...and he's next! Blackjack eventually explains that the boy has a terminal illness, and the hospital personnel and mother were just walking on eggshells trying not to let him know. Fortunately, Blackjack is there to cure the illness.
Senna of the first Bleach movie is horrified when she learns herself to be nothing more than the merged memories of the Blanks. The trope is zigzagged as she refuses to accept that she never actually existed and her dying request is that Ichigo take her to her grave, which is proof of her existence. Even though the grave does not exist, Ichigo chooses to tell her it does so she can die happy having never accepted the truth about herself.
Senketsu learns that he's an alien, which he doesn't really mind. However, what triggers the Heroic BSOD is when he learns that his species, Life Fibers, sees humans as food, and he realizes that he had been feeding on Ryuko all along, since he needs to drink her blood to activate his powers.
Later, Ryuko learns that she's a human/Life Fiber hybrid. And her mother's a complete monster. She goes mad from the revelation for a while.
Neon Genesis Evangelion: You know those alien monsters humanity has been fighting throughout the series? Humanity is one of them.
The Firesign Theatre, in their comedy album I Think We're All Bozos On This Bus, uses this device ingeniously. One must listen carefully (or have seen a spoiler) to realize that the character "Clem" who finishes the story is not the one who started it, but rather a holographic clone created by the original Clem and then dismissed into cyberspace.
In the Big Finish Doctor Who audio drama "The Natural History of Fear", characters with the voices of the main cast live in a totalitarian city with its own version of Doctor Who. The listener is led to believe throughout the audio that the Doctor, Charley, and C'rizz have had their memories wiped and are trapped by the city using the roles they are placed in, the Editor, the Nurse and Conscience #1, respectively. However, at the end of the audio, when the Editor sees the memory of the Doctor and companions visiting Light City and the Doctor having to give up the group's memories to the city, he finds out the memories were only copied. The group only was in Light City for a day and the characters seen were created using their memories, revealed to the listener when the Editor mentions he has eight legs.
In "Brave New Town", the inhabitants of the Uncanny Village all turn out to be plastic Autons with real emotions and a Weirdness Censor. This was later also used in series 5 of the revived TV show proper.
In "The Holy Terror", the little boy has the same face as the scribe.
The plot of the Spider-ManClone Saga was going to originally resolve itself in this way, with the "clone" Ben Parker finding out that he was the original, while the "original" Peter Parker, whom comic book fans had been reading about since the original clone story in the '70s, would be revealed to actually have been the clone all along. And then Marvel Comics chickened out... (After the infamously long Clone Saga went back and forth at least a half-dozen times about which Spidey was the clone.)
The JLA's initial way of dealing with the White Martian threat was to hypnotize them into thinking that they are mere humans. This leads to an issue where Batman declares that several members of the JLA need to track down a great threat to the world: Bruce Wayne. Turns out that one of the brainwashed Martians was working for Wayne as an assistant. After being involved in a plane wreck it loses its memories again and decides (from papers it had) that it is Wayne and takes his form (making it a double example of this trope: a Martian who is forced to think it is human who then winds up thinking it is a different human).
an even tighter fit for this trope is the revelation that Elijah Snow and all other Century Babies aren't human, they're a kind of meta-world antibody created to help humanity and as a result, have no soul. Elijah takes it surprisingly well.
In Rising Stars, Poet asks Clarence Mack what he knows about the murders of the other Specials. Clarence discusses his own theories and uses his ability to enter the minds of others to show Poet his findings, when he realizes that he saw exactly who the killer was, and was murdered only moments later for it. And that, while he was unaware of it until just now, he's only having this conversation because another Special who is a medium summoned his ghost.
The Kevin Smith comic Green Arrow: Quiver features the titular hero, Oliver Queen, returned from the grave. This seems at first to be a typical comic book resurrection, but why does Oliver seem convinced that he never died at all, that everyone else is acting very odd, and that cellphones and modern computers are the sort of things only supervillains possess? Turns out that this is Ollie's body brought back to life, minus his soul. The Spectre wanted to resurrect him, but his soul was happy in heaven. So they compromised; Oliver's body was given new life, but with ten years of his history removed to avoid all the Wangst he would have otherwise gone through (as his life was in shambles when he died). In the end his body and soul are reunited, returning Ollie back to life for real this time.
A number of Skrulls believing themselves to be Marvel heroes have a bit of an identity crisis meeting their human counterparts during the Secret InvasionCrisis Crossover. Particularly Khn'nr, the Skrull impersonating Captain Marvel, who never actually recovered his proper memories. Upon finding out he was a Skrull, he instead fought against his own people.
In an early issue of The Sensational She-Hulk, our titular green goddess wakes up to see her headless body being used to provide a new mode of transportation for Chondu the Mystic's head. It turned out to be a cloned body, though. They couldn't find a saw that was able to cut She-Hulk's hair, let alone through her neck.
There's a short Marvel comic called "The Creature". A man finds an alien's diary and runs around trying to find someone who'll believe him. The random guys on the street don't believe him. The policeman doesn't believe him. The soldier guarding a military base tells him to take it to the observatory. The man rushes to a scientist there, hands him the journal. The journal is written in an "unearthly scrawl" which only the person who wrote it could read.
In the second issue of Alan Moore's run on Swamp Thing, the titular character learns that he isn't Alec Holland. He's just a sentient plant that absorbed Alec Holland's memories, and his years of searching for a way to regain his humanity were pointless because was never human in the first place. This sends him into a majorHeroic BSOD. Turns out Alec isn't Alec after all
This trope was played with throughout the first half of Doom 2099. Doom claims he jumped to the future due to a failed experiment, which also damaged some of his memory. People note strange discrepancies at first (he's too young, his face isn't scarred [at first], etc). Then Doom learns he was the son of a political enemy to Latveria, who was kidnapped by the REAL Doctor Doom and Brainwashed into thinking he was the real Doom. Then it gets massively subverted. Doom really was the real deal; his youth and failed memories were because of a regeneration tank. There was no Gambit; it was just Doom's former lover getting bored and screwing with him.
Machine Teen is initially unaware that he's a robot. When he's injured at school he refuses to accept that he's not bleeding, and when he's forced to aknowledge it, he immediately shuts down while the knowledge is deleted.
In an early Post-Crisis story, Superman shows up badly damaged somehow having been turned into a robot Superman. It turned out, of course, that this really was just a robot Superman who was so well programmed that he genuinely thought he was Superman.
The My Little Pony: Friendship Is Magic fanfic Crisis Equestria features a set of antagonists that are evil clones of the mane six. They were unaware of this. When it gets revealed to them, it generates a mass Villainous BSOD on all fronts, the end result being that they decide to kill their originals to prove themselves the superior versions.
In Clash of the Elements: Driad is not a Good Guardian, but actually the former Outer Guardian of the Nature Castle
This is subverted with Luigi and Dimentio in Part 2 though.
In a way, this happens to Fluttercruel. She believed she was Fluttershy during the events of "The Return of Harmony", only to discover she's a spiritual clone of Fluttershy created by Discord after Twilight used the Memory Spell on her.
In the Shining Armor Arc, Shining Armor eventually discovers that he literally didn't exist before his story started, and his timeline's been filling itself in both ways ever since. This is why he's Immune to Fate, why Makarov'sCharm Person abilities don't work on him, and why the Wolf is after him.
Navarone ponders the nature of his existence in Diaries of a Madman, after going back in time and meeting his past self. While he comes to the conclusion that he's real, the uncertainty over whether he's a clone, or what exactly he is weighs heavily on his mind.
Pokeumans: Any transformed Pokeuman is replaced by a clone who lives out their human life believing they are the real one. If any of the Recursive Fanfiction series have them discover their true nature, they're in for a hard time. Luckily, the community is pretty well recognising that Clones Are People Too
While My Little Pony: Friendship is Witchcraft itself never sees her realize it, many fanfics based on it deal with Sweetie Belle learning she is a robot, as well as learning to deal with the revelation.
Toy Story: Buzz Lightyear. Consider the implications of realizing that you're not a Space Ranger, not a human being, the universe you remember doesn't exist: "YOU! ARE! A! TOOOOOOY!"
In Cars 2, Mater is told that everyone sees him as a fool, and then looks at his reflection. Get it? Tow Mater in the mirror!
Mater: Is that how you see me?
Finn McMissile: That's how everyone sees you, and that's the genius of it. Nobody realizes they're being fooled because they're too busy laughing at the fool.
Meet the Robinsons: A young boy named Cornelius "Lewis" Robinson befriends a boy named Wilbur, who apparantly came from the future. It is later revealed that Lewis is actually Wilbur's father.
At the end of Sintel, the title character sees her reflection in the blood of the dragon she just slew and realizes how long she's spent on her quest for revenge. She's no longer a teenager, but an older woman with graying hair. And her friend the baby dragon had also grown up...
Films — Live Action
The Twist Ending of The Sixth Sense is a relatively subtle example of the trope; the main character has no idea that anything is odd about him, as people's reactions to his words and actions seem entirely plausible, until he realizes that they only appeared to have been interacting with him in the way he expected them to. The fact that everyone's reactions seem plausible is even lampshaded ahead of time, when Cole tells him that ghosts only see what they want to see, and hear only what they want to hear.
The 6th Day, where the "cloned" Arnie turns out to be the original.
The 2003 Indian Bollywood film Darna Mana Hai, starring Shilpa Shetty, takes this trope almost literally, withapples.
Played straightforwardly in 2008's The Broken, where Lena Headey's character kills her doppelgänger and then spends the movie running away from the evil mirror clones who have taken over all the regular people. And then the twist ending happens.
Nicely done in The Others. Grace Stewart finds herself in the midst of a haunting, only it turns out she and her family are the ghosts; the "spooks" they've been seeing are actually the living family who've come to see about buying the house. Particularly unsettling is the publicity clip where the creepy old woman talks to Grace in her daughter Anne's voice — when one realizes Anne's soul is actually possessing the woman, a medium hired by the living family.
In Angel Heart, Mickey Rourke's character, a private detective, turns out to be the very man he's been hired to track down.
In Salvage, Claire Parker seems to be living a Groundhog Day-esque nightmare where she keeps getting stalked and killed by serial killer Duke Desmond, only to wake up back at work as if nothing had happened. After a non-fatal attack, she learns from the police that Desmond can't be stalking her, since he's been dead for some time. She decides maybe it's his ghost that's tormenting her, and seeks advice on how to deal with that. The first place she visits just happens to be Desmond's former church, where the janitor reassures her that Desmond can't hurt her, as he's in hell. Not reassured, she goes to his old home, and then the library, where she finds a newspaper article showing that she and her boyfriend were his last victims. Eventually, Desmond appears in her house to kill her yet again, and now she's finally told the whole truth — she isn't Claire. She's Duke Desmond, whose punishment is to keep reliving his murder of Claire, from her perspective.
Fight Club is a masterful example, as Edward Norton's unnamed narrator befriends and starts Fight Club with Brad Pitt's Tyler Durden, anarchist and soap salesman. As Durden begins to raise an army of committed nihilistic followers, the narrator becomes less and less comfortable with the direction of the movement. After Tyler Durden disappears at the kickoff of a coordinated act of domestic terrorism, the narrator hunts desperately for him, only to be told that he is himself Tyler Durden. The revelation changes the tone of previous conversations in the film, notably the inception of Fight Club — what was a brawl between the narrator and Durden that attracted other participants becomes the narrator/Durden beating himself up, rousing the curiosity of others. And Durden's intense sexual relationship with Marla Singer coupled with the narrator's open contempt for her; what were the actions and reactions of two separate characters take on a different light when you know the characters are the same person, and Marla's confusion and hurt at the narrator's scorn makes more sense. In the end, the narrator shoots himself through the cheek, "killing" Durden by demonstrating he was willing to kill himself.
Subverted, and possibly double-subverted in The Thing (1982). For a while, it really looks like Mac is The Thing. And then he's revealed not to be. But in the final scene, it's starting to look like he could be. If so, he hasn't been for long, though.
The Cabinet of Dr. Caligari. Once you understand that Francis is a nut, and Cesare and Caligari aren't even their real names, everything makes a lot more sense. Including the art style.
In the original ending everything was to be taken at face value. The producers suggested a change because they suspected the Weimar censors wouldn't allow a movie that implied an authority figure could be evil.
Dead & Buried. The sheriff of a small town discovers that several strangers passing through town and many of the townspeople, including his own wife, have been murdered and turned into zombies by the town's mortician. At the end he confronts the mortician and learns that he himself suffered the same fate sometime earlier. What is more, it's implied that he's investigated the killings dozens of times before, his memories being wiped each time he learns the truth, because the mortician enjoys playing mental chess games with the sheriff.
Jacobs Ladder. In a deleted scene, Jacob finds out that Jezzie was actually himself, when he unmasks the shroud she's enveloped in.
The Neverending Story. When confronting his "true self" in a mirror, Atreyu sees Bastian, the boy reading the book, as his reflection.
Impostor. Gary Sinise's character is, in fact, the robo-bomb he's been trying to prove he isn't for the entire movie. His wife is one, too.
Literally in the Bittersweet Ending of Mirrors. Ben leaves the Mayflower building after having defeated the demon, but none of the emergency workers seem to notice him despite his injuries. It turns out that he is trapped in the mirror world.
In the original Korean version Into The Mirror, Young-min gets trapped inside the mirror world but doesn't realize it because nothing is different...except for the fact that everything is backwards/mirrored.
Depending on the version of Blade Runner you watch, either Deckard or just Rachel is a/are replicant(s), and going to snuff it fairly soon, or live happily ever after. However, since both Rachael and Deckard (if he is a Replicant after all) are next-generation experimental Replicants, it doesn't neccessarily mean they'd have the same four-year lifespan as the Nexus-6 series.
The ending of Hellraiser: Inferno reveals that the being known as the Engineer that Detective Joseph Thorne was after is in fact the embodiment of his own dark urges; when Joseph confronts the Engineer the thing even peels away its blank face to reveal Joseph's underneath.
In Terminator Salvation, Marcus Wright finds out halfway through that he is a modified cadaver used to outfit a prototype infiltration Terminator. The converse situation occurs in an episode of The Sarah Connor Chronicles where the Terminator Cameron believes she is a human girl.
In Takashi Shimizu's Reincarnation, the story begins with a college professor filming himself as he brutally kills a hotel full of innocent people, including his own children, because of his obsession with reincarnation. Thirty-five years later, some creep decides to make a movie about it, and sets out to cast the killer and his victims. So what? So plenty. He succeeds, managing to cast the reincarnation of everyone involved in the massacre. The main character realizes she ties into all this, but doesn't find out how until the end of the movie, when she sees her true self in her reflection.
In Police Academy 6 it soon became clear that someone in the group was leaking information to the mastermind behind the crime wave; as always, Captain Harris figured it was one of the heroes, and started an investigation to find out who. As it turned out, the mastermind was the mayor, whom Harris was communicating with, meaning that Harris was unknowingly the leak, because he thought by giving the mayor information, he was helping oppose the mastermind! (The mayor's charade does not exonerate Harris, however, because everyone on the team was told to specifically tell nobody, a rule which Harris was breaking because he figured - wrongly - there'd be no harm telling the mayor.
As seen in this video, in the film Transmorphers the main character is eventually revealed to be an android. The reviewer had this to say-
The film Shattered follows a man who survives a car accident with amnesia. Along the way he discovers that his wife was having an affair. She explains that she didn't say anything because she didn't want him to remember killing her lover. When he finds her lover's corpse, it looks just like he does after the doctors repaired his face to look like the photos of the man they believed he was.
In Unknown2006, several men wake up in a warehouse with toxic-vapor-induced amnesia. They discover that some of them are kidnappers, and at least one of them is a kidnappee, but they don't know who's which. The protagonist hopes he's not one of the villains, and the gradual return of his memories eventually reveals he's an undercover cop. This comes as a great relief ... until, at the end, he catches sight of the kidnapped man's wife, regains his memory of the affair he's been having with her, and realizes that he'd gone to the warehouse to kill her husband so they could get married and the kidnappers would be blamed.
In the 2011 film Unknown, Dr Martin Harris wakes up from a four day coma after a road accident to find that another man has completely taken over his life and identity, to the extent that the impostor has the same family photos and is believed by his wife to be the real Martin Harris. Harris decides explore what happened in the four days he was unconscious, eventually discovering that "Martin Harris" is not a real person but a cover story - Martin and his "wife" are undercover assassins, and the "impostor" is another agent sent to replace him after the accident, the trauma of which caused him to believe his own cover story.
In Moon, the protagonist, after spending 3 years on the moon, finds out, that he is the 5th clone to work the station, and all his memories of the time before he was there are implants. Together with the 6th Clone, they also find out that 'their' daughter, who they thought was a newborn, is actually 15 years old, and that they and the other clones are programmed to die at the end of their 3-year contract. The station has hundreds of clones ready to be woken up in a hidden room.
In The Da Vinci Code, Sophie discovers that she is the possible descendent of Jesus whom she and Langdon have been speculating about.
Passengers: Claire, a therapist counseling a group of plane crash survivors, grows suspicious when her patients start disappearing, and she suspects that the airline is behind it when a mysterious man starts coming around and insisting that the crash was pilot error. Meanwhile, others insist they heard an explosion beforehand. Claire takes on the mission of finding out what really happened while trying to protect her patients from what she believes is a corrupt airline. It turns out that Claire was actually on the flight also and there were no survivors. The reason the patients are disappearing is because they accepted their deaths and are moving on. The mysterious man is the pilot, also dead, and he blames himself for the crash because he was distracted and tired, hence "pilot error."
The original ending of the 2007 film version of I Am Legend fits into this trope, at least metaphorically. It had the main character realizing that the infected were actually intelligent and capable of love/compassion/etc., and had only been coming after him because he was kidnapping, experimenting on, harming and killing them in an effort to "cure" the disease; the 'leader' of the infected merely wants his mate back, and the various attacks had been acts of self-defence. Will Smith spent the movie believing that they were mindless monsters when, in fact, he was the monstrous one, albeit unknowingly. The title refers to this, as he's the boogey man in the infected's legends — hence, "I Am Legend". This was the ending in the book as well.
At the end of The Deaths of Ian Stone Ian Stone turns out also be a Harvestor instead of the normal human he thought he was.
Frailty has two such twists. First is the discovery that the man the FBI agent has been talking to for most of the film isn't Fenton, but Adam. At the very end of the movie, you find out that Adam and his father aren't crazy, they really have been charged by God to destroy Demons walking the Earth.
The Machinist has Christian Bale's character Trevor, who hasn't slept for nearly a year, stalked and tormented by a man named Ivan. Ivan eventually kidnaps Nicholas, the son of the woman Trevor is (sort of) dating. Ivan appears to have murdered Nicholas, causing Trevor to kill Ivan. When disposing of his rug-wrapped body, it unrolls and is empty. Trevor then remembers that "Nicholas" was actually a nameless boy that he had killed in a hit-and-run himself a year ago.
The Moebius strip of a film known as Triangle does this in numerous ways throughout the movie, which largely consists of a repeated sequence that reveals more of its story every time, each time arriving at a Memento-like "how we got here". This story includes Melissa George's character running from a masked killer who turns out to be herself, turning into that killer in an effort to evade her, trying to warn away doppelgangers of herself and her friends, and eventually killing her own Evil Twin doppelganger.
After Wynn is captured at the end of Cube Zero, Jax reveals that Wynn is NOT an employee overseeing the cube. He's just as much a lab rat as the Cube residents, as another layer of the Cube experiment to "observe the observers". So were his colleagues. He can't even choose execution over staying in the cube, as he already waived this right long ago... he simply doesn't remember because the real operators removed this information from his mind.
The classic The Creation Of The Humanoids plays this to the hilt. After the End, humanoid robots are all that allow the small population of human survivors to maintain their civilization. Fearing a Turned Against Their Masters scenario, the humans despise and fear the robots, and even have the Nazi-like "Brotherhood of Flesh" that seeks to expose robotic treachery. They think they're on to something when they discover a highly illegal 'Type 98' robot that thinks it's a specific human, and an additional memory module that causes any robot it's plugged into to think it's that human. The Reveal is that this is the result of a completely benevolent conspiracy between the robots and a human scientist to devise a way to transfer human minds into immortal, self-reproducing 'Type 100' robot bodies at the death of their organic bodies, and the protagonist (who leads the Brotherhood) and his new girlfriend have both been through the process already.
Subverted in the 2008 film "The Lazarus Project" (originally "The Heaven Project") when Ben Garvey eventually accepts that he is a patient at the psychiatric hospital but then, after finding his supposedly hallucinated dog at the local animal shelter, finds that it was a plot to stop him leaving.
Eden Log. After not even knowing his own name throughout most of the film, the man discovers that he is actually Tolbiac, the chief of security of Eden Log.
Oblivion (2013) : He's not the real Jack Harper, but a clone. He works for the Tet, which is stealing the planet's water for fuel. And he's just one of many (we follow the 49th, which fights the 52nd later on, and Beech mentions that the Tet used an army of Harper clones as foot soldiers during the war).
In Ruby Sparks, Calvin keeps it a secret that his girlfriend Ruby was a fictional character who came to life. When she finds out, it is not pretty.
Donnie Darko. The lead character has visions of a man named Frank who wears a large grotesque rabbit suit and claims to be a time traveler. Following Frank causes Donnie to avoid being killed by a Jet Engine that falls from the sky. Frank instructs Donnie on the actions he must take in order to save the future. The plan involves a metal artifact that will serve as a Deus Ex Machina, a resolve to the central conflict of the plot. Donnie locates the artifact in the form of a gun. Donnie uses the artifact to shoot the man who accidentally hit Donnie's girlfriend with his car. The scenes that follow reveal that the man Donnie shot was in fact Frank, that the tragedy of his girlfriend's death was the result of his own actions, and that the artifact that will save everyone is not the gun that Donnie found but the Jet Engine that must fall on Donnie Darko, to avoid the tragedies of what would follow had it not. The Jet Engine itself being a time traveling artifact that would have fallen off the plane Donnie Darko's family would have been on, if Donnie had survived. Thus, revealing at the end that Donnie Darko is the villain of this story, and he must save the future from himself.
In Frozen Days, the main protagonist’s true identity seems to vanish as she assumes that of a comatose man. It turns out in the end that she was the comatose one the whole time.
In The Ward, Kristen is institutionalized under mysterious circumstances, and quickly becomes aware that something strange is going on in the psych ward: She's visited in the night by a ghostly woman, the fellow female patients she's befriended keep disappearing mysteriously whenever they show signs of improvement, and the staff refuses to speak of what happened to the other girls or admit that anything is wrong. Her friends are only slightly less cagey than the staff, but eventually reveal that they had killed a fellow patient named Alice, whose vengeful ghost is now murdering them. But while attempting to escape, Kristen learns that she is Alice, or more specifically her latest Split Personality - the other girls are also Alice's multiple personalities, they "killed" Alice via Split Personality Takeover, and they're disappearing one by one because of an experimental hypnosis treatment that's eliminating her personalities one at a time.
Stephen King probably has more than just the one, but an early story, "Strawberry Spring," (published in the collection Night Shift), has something like this happen to the narrator, who realizes he has a dissociative serial killer personality that only emerges during the fogs of titular "Strawberry" springs.
Shutter Island. Teddy Daniels is Andrew Laeddis, who killed his wife after she drowned their children. He has been searching for Laeddis throughout the novel only to find that he IS Laeddis under a horrible delusion. Maybe.
One of the earliest examples is "The Outsider", a first person point-of-view story that follows a mysterious lonely individual who cannot remember coming in contact with people. When he escapes his tower, he scares off the first people he sees and spots his reflection, revealing him to be — ta-dah! — undead.
And again in his story "Facts Concerning the Late Arthur Jermyn and His Family".
In the story "To Mars and Providence", published in the anthology novel War of the Worlds: Global Dispatches, this happens to Lovecraft himself; he discovers he's actually one of the elder gods whose eventual return forced the Martians to flee their homeplanet and invade Earth.
Philip K Dick used this trope frequently as both a device and a premise. Perhaps the best-known example is is the film Blade Runner, very loosely based on his novel Do Androids Dream of Electric Sheep? Arguably, this is also the premise of A Scanner Darkly, although in this case the twist is identical with the character arc. And never forget the short story "Imposter", in which the enemy plot revolves around the character finding out he's an android. The trigger phrase for the bomb inside him is "...then I must be the..."
J. G. Ballard was also fond of this device, and employed it in his 1960 story "Zone of Terror."
In Frederik Pohl's science fiction "The Tunnel Under the World" the main character becomes convinced that some sinister conspiracy is keeping the citizens of his town stuck in a "Groundhog Day" Loop by erasing their memories every night. He eventually learns that he and everyone else in the town were killed in an explosion, and their consciousnesses have been installed into tiny androids in a scale model town where they repeat their final day over and over while researchers use them to test the effectiveness of advertising jingles and political slogans.
A Shocker On Shock Street: A kid whose father is a horror movie director is menaced by horrible things; turns out he's the robot star, and the whole thing was part of the movie.
You also have The Ghost Next Door, in which the girl suspects ghosts only to find out that she's the ghost.
My Hairiest Adventure: a kid starts growing hair after trying some instant-tanning lotion. He thinks there's something wrong with the lotion and he's turning into a dog as a result, but everyone insists the stuff is harmless. Turns out it is, he was born as a dog, and so were all the other kids in the town. The adults are involved in an experiment to turn dogs into people, but it's starting to wear off...
Another book by the same author (though not part of the Goosebumps series) involves a kid who is convinced that everyone he knows is being replaced with a duplicate, a la Invasion of the Body Snatchers. Turns out at the end that he is a robot, and his memory chip is malfunctioning.
Another classic one, The Girl Who Cried Monster, is a girl who finds out that her librarian is a monster. At the end of the story, she finds that her parents are monsters too...and that she and her brother will eventually get their training fangs.
A similar twist was in Vampire Breath, where the protagonist finds that the vampire he woke up is actually his grandfather. In the live-action adaptation, he and his sister even gets fangs and coffins at the end of the episode.
I Live in Your Basement, one of the last in the original series, tells the story of a boy whose stalked by a possesive, inhuman entiy that lives in his basement. The end reveals that the monster is the narrator, dreaming that he was in the shoes of the kid upstairs.
The short story The Werewolf's First Night features a boy being terrorized by a pack of werewolves. It turns out that they're really humans playing a mean prank on him... but he discovers he actually is one. He then uses this chance to get some revenge and chase them.
In the novel John Dies at the End, while dealing with a conspiracy involving agents of a parallel universe, the protagonist/narrator David discovers self-incriminating evidence and catches a glance of what appears to be a dead body in his tool shed. He can't remember a half-hour or so of his day, while his gun is missing a single bullet. He also finds out about a young woman, Amy, who went missing around the same time. He immediately suspects he murdered her during a bout of temporary insanity, but while following clues, he discovers that she's alive and well, but can't remember anything from when she went missing. He later learns that those conspiratorial agents are in fact perfect clones that have replaced other people in the city. Over the course of a few days, he uncovers some very unsettling information, protects Amy from the forces of darkness, falls in love with her, travels to the parallel universe with his best friend John, and cripples the organization behind the invasion. When he finally takes a good look inside his tool shed, he discovers a corpse that looks exactly like himself. Assuming that this corpse was an intended replacement that he shot in self defense and blocked it out, he goes to reveal the identifying mark of the clones on the bottom of the body's foot. When the mark isn't where he expected to find it, Dave checks his own foot and learns that he is the clone, and personally killed the original Dave. At first, he's suicidal with guilt, but since he is completely indistinguishable from the real Dave in every way (aside from the mark on his foot that regular people can't see) and anything that would have controlled him is now dead, John and Amy manage to convince him to go on living his life as if nothing had happened. Except for his friend John occasionally calling him "Monster Dave" as a joke.
Done twice in the Crucible trilogy by Sara Douglass. First, the protagonist goes out to return the demons to Hell — only to find out that both his wife and best friend (and soon-to-be-king) are demons. Then, when the antagonist role shifts to the angels, he discovers he is an angel too, and thus doomed to send all mankind into eternal slavery. Poor Tom.
Appears in Hunter S. Thompson's seminal work The Kentucky Derby is Decadent and Depraved, wherein the main character and his foreign photographer searches Kentucky during the annual horse race derby for the very poster child of the decadence and depravity associated with the derby. In the end, after four-five days of madness, culture shocks and innumerable amounts of alcohol, his photographer exclaims: "It's us!"
Subverted in Breakfast of Champions wherein a man of declining mental health becomes convinced that failed Sci-Fi writer Kilgore Trout's short story really is a letter from God revealing his Tomato in the Mirror status.
Sabella by Tanith Lee ends with the reveal that she and the main male character are both native Martian copies of human children who died in a certain underground cave.
Done excellently in the Dragon Lance short story "The Best." It is done in first person, with the narrator being a noble who's hired the four best dragonslayers in the land to kill a dragon who's been terrorizing the countryside. At the end of the story, they reach the dragon's lair, and it's revealed that the narrator actually is the dragon in a magical disguise, and he's gathered them all together to take them all out at once, so he can sleep in peace. And it works.
In First Among Sequels, when Thursday1-4 is impersonating Thursday the second time, the first person narrator actually switches to Thursday1-4, so even the audience is fooled... until she starts thinking about her villainous plot again.
Goliath, the evil corporation, replaces people with synthetic versions on such a regular basis that the Genre Savvy characters check themselves frequently to make sure their still . . . them.
Lord Dunsany's short story "The Return", in which the narrator—who promises a real ghost story—only discovers at the end that he is the ghost. (Also broadcast as a radio play.)
The short story The Copy by Paul Jennings features a copy machine (which creates a mirror-image replica of objects put into it) which a boy uses to copy himself so he can beat down a bully, but becomes jealous of his copy and kills him. Afterwards, his mother remarks that it's odd - his mole used to be on the other cheek, and he's writing with his left hand instead of his right...
This is the plot of the Deep Space Ninerelaunch novelFearful Symmetry, told first from Captain Kira's perspective, then from that of her double, Iliana Ghemor, a Cardassian sleeper agent altered to look like Kira and remember being her. In the novel, Ghemor is the tomato; in the Deep Space Nine episode it was a sequel to, the tomato was not Kira.
Alastair Reynolds does this a lot in the Revelation Space novels. Chasm City offers a particularly convoluted example: Our lovable hero Tanner is actually the war criminal Cahuella, after stealing Tanner's identity and buying into his own cover. Cahuella experiences flashbacks of the life and times of the near-mythological psychopath Sky Haussmann, and believes them to be the result of the indoctrinal virus he is infected with. Actually, he is Sky Haussman.
In Nick Harkaway's The Gone-Away World, a Crapsack World in which a super weapon poked big holes in the time-space continuum and which is held together by Applied Phlebotinum the narrator tells the story of himself and his best friend Gonzo and how the world came to be. About halfway through when the story shifts to present tense we find out that the narrator is Gonzo's imaginary friend who has been made flesh by an accident involving said phlebotinum.
In Harry Potter And The Order Of The Phoenix, Harry believes himself to be the tomato when he overhears members of the DA mutter something about him being possessed by Voldemort. As he'd just witnessed/felt like he'd actually attacked the father of his best friend, he is terrified of the possibility that he'd been the one attacking people. He wasn't.
Towards the end of the series, Harry realized that he is a horcrux. For Voldemort to die, Harry himself must die because he is what is holding Voldemort to life. The reverse is also true, so Harry doesn't die, because Voldemort destroys his lifeline first and then gets killed. This is why the prophecy stated that "neither can live while the other survives." Also, Harry realizes this is the reason for the similarities between himself and Voldemort...because he IS Voldemort, at least partially.
The Star Wars: Galaxy of Fear book Clones features, you guessed it, clones. Possibly subverted. Tash Arranda flees a horde of evil clones of herself and her brother, sheds her own clothes and dons one of the jumpsuits they're wearing, and hits her head so the past few minutes are blurred together and confusing. She finds a defective Tash-clone that thinks she is the real girl and the others are after her. Since they seem to have her memories, Tash freaks and wonders for a while if she isn't a defective clone herself. Soon enough she decides she's not. For one, only she has the necklace her mother gave her. For two...
Tash remembered the two clones of herself that she'd met. Both had known everything she had known. But they were still different from her. One had been angry, almost evil. The other had appeared frightened and defeated. The real Tash had been bothered by the sense of the dark side, but the first clone must have been totally absorbed by it. Later, Tash had been frightened by the army of clones, but the second clone had been petrified.
So they weren't exactly like her. They couldn't have the same feelings. They hadn't had the same experiences, just memories of those experiences. The feelings attached to them were absent.
Played straighter in an earlier book, City of the Dead. In that book, injecting a corpse with a certain serum and exposing them to boneworm slime caused them to rise as a zombie. The Mad Scientist looking into this also found that injecting himself with the serum before he died, and then getting bonewormed after death, made him come Back from the Dead as a zombie with all his memories and facilities intact, though he did tend to twitch. Then, trying to eliminate the twitch, he injected Zak Arranda with the serum, poisoned him into a coma so deep he was declared dead and Buried Alive, and therefore had him exposed to boneworms. Later Zak categorically denied that he was now a zombie, since he was still alive and actually had never died, and he doesn't have the Super Strength of these zombies... but he does twitch a little at the end of the book. Maybe this means that he'll come back after he actually does die.
Ted Dekker's Christian suspense novel (and later movie)Thr3e is about a young man tormented by a serial killer that decides to make him his next victim. He's aided by an old childhood friend and an FBI agent whose brother was one of the victims. It later turns out that both the "killer" and the childhood friend are alternate personalities of the main character, caused by the abuse his adoptive mother put him through as a child. In fact, the "evil" side of his personality isn't the same serial killer that killed the agent's brother at all—the main character heard about the murders and his other personality started to copy them.
This is also the plot of Sidney Sheldon's Tell Me Your Dreams and several other books and movies.
At the climax of The Demon's Lexicon by Sarah Rees-Brennan, Nick, the protagonist, learns that he's not human—he's actually a demon who was bound into the body of an infant and grew up thinking it was his own.
A rare happy example of this trope: throughout Terry Brooks' Magic Kingdom for Sale--Sold!, Ben Holiday spends the novel trying to find a way to summon the Paladin, the invincible champion of the kings of Landover, only to discover when he is finally successful that he himself is the Paladin.
Older Than Radio: Used in the 1839 Edgar Allan Poe short story "William Wilson," wherein the titular Villain Protagonist discovers that the mysterious doppelganger that has been constantly foiling his schemes is himself, or rather the personification of his conscience.
This happens in The 39 Clues, at the end of Book #7 - "The Viper's Nest". Near the end, they discover that Amy and Dan are Madrigals.
The urban fantasy book White Apples by Jonathan Carroll has an enemy mook who is ordered to a barbershop to meet the King of the Park, a notoriously dangerous bad guy. As he enters the barbershop, he is terrified, desperatey trying to figure out which of the people present is this nasty character, until it is revealed that the King of the Park is not a single person, but a series of people who have been given his power; the people in the barbershop are there to transform him into the King of the Park, until the end of his mission.
The young adult series Mindwarp has one of these. The kids at the core of the series, teenagers with superpowers who're hunted by alien shapeshifters, often make reference to Todd, a kid who vanished from their small town before they started coming into their powers. Come book 5, Todd shows up back in town; to him, there was a bright light one night, and he returned several months later with no knowledge of the intervening period. Surprise — he's actually an alien shapeshifter on very, very deep cover trying to flush the kids out. He defies his programming, however, and disguising himself as one of the other kids so the aliens take him instead. The trope is also played with every kid in the series. They're part aliens too.
In Wonderland by Joanna Nadin, what was designed as a clever plot twist was actually made pretty obvious to the readers. The main character begins about to kill herself and her best friend, encouraged by that friend. Then the story is told in flashback and she realises she IS her best friend. She has Dissociative Identity Disorder, apparently. Many readers called it, especially since NO ONE else interacted with the friend, and the main character hid all reasons why she went to see her, and so the plot twist was no longer there.
Before I Go To Sleep by S.J. Watson is about Christine, a woman who each day forgets everything that has happened to her for years (she is in her 40s, but cannot remember anything since her early twenties). Each day, her husband (who she does not recognise) explains to her what has happened to her, why this is the case, and what happened to her to make her like this. Later, she meets a doctor, who suggests that she keep a written journal (a film journal in the movie) to keep some sort of day-to-day continuity. Through this, and further meetings with the doctor, she discovers that her husband has been lying to her about parts of their past; he explains this as embarrassment about certain events, as well as an inability to cope with having to explain too much to her every single day; the reader is led to believe instead that he is abusive, unfaithful husband who is using Christine's amnesia to hide a dark part of their relationship. However, the eventually revealed reality is even worse; he is not her husband at all, but a sociopath who has abducted her and used her memory loss to convince her of his false identity as her husband. Furthermore he is the one responsible for her condition; they previously had an affair, and when she broke it off he viciously beat her and left her for dead.
In The Adoration of Jenna Fox, the titular character Jenna wakes up from a year-long coma after an unspecified accident with no memories of her life. Her parents say that she'll remember with time, and she does begin doing so, but it doesn't take her long to realize that something's off, something her parents are hiding from her. The Reveal is that 90% of Jenna is artificial and only 10% of her brain is from her old self. Oh, and the operation to give her a new body after the car accident is illegal, which is why her parents are hiding out in a secluded place. She even says "I'm not a tomato" at one point; it does make sense in context.
A variant of this trope occurs in the World War Z supplement Closure, Limited. The interviewer is given what appears to be a tour of the titular organization, which provides closure for customers by dressing up a zombie to look like a loved one and kill it. The interviewee goes at great length to explain the detail they take, flat-out explaining that his customers generally know that the end-product isn't really their reanimated loved one, but the need for closure is so great that they don't care. it's hinted at the end that the Interviewer isn't really an interviewer: he's a customer, and at the end, he shoots the zombie they dressed up for him.
In the Magic: The Gathering short story collection Shadowmoor, one of the stories is "Meme's Tale," in which the titular heroine is forced to flee her goblin family, and has no idea why they exiled her until she glimpses her reflection in a pool and sees that she's an elf.
Mira, the only human character in Rick Griffin's Argo, finds out at the climax that she, as well as most if not all the human race, is an android.
At the end of Diana Wynne Jones's Archer's Goon, Howard Sykes finds that he is Venturus, and that he's keeping all his siblings stuck in one place in time and space.
In the Otherland series by Tad Williams, one of the many charcters you follow is Paul Jonas, a man who has lost his memeories. He picks up bits an pieces over the first three books, but in the last one finally discovers not only his past, but that he is a digital clone of the real Paul Jonas.
Done in a Sesame Street book, of all places! The Monster at the End of This Book has Grover being terrified of the title character and pleading with the reader not to reach the end of the book and reaching the monster. Hilarity Ensues as Grover tries increasingly drastic measures to prevent the reader from reaching the end of the book. When the reader finally reaches the end, Grover thinks he's doomed...but then he realizes that he is the monster at the end of the book. Go figure.
In Neil Gaiman's novella "Murder Mysteries", the main character turns out to be a disassociative serial killer who doesn't remember his crimes, or that anything is wrong at all, until after he's told about a murder investigation that happened in heaven prior to the creation of the universe, by an old man who may or may not have been the Archangel Raguel, whose function is to serve as the Vengeance of the Lord.
In the O. Henry story "A Man About Town", the protagonist is obsessed with learning more about people, particularly stereotypes like the titular "Man About Town". He questions people, including a learned friend. His obsession causes him enough travel and tunnel vision that he has a traffic accident. In the hospital, he reads a newspaper article about the accident where the victim is described as a "typical man about town."
In Mira Grant's Parasitology, the main character, Sal, is a tapeworm who has taking control of her host's body. An astute reader will figure this out considerably faster than Sal does, but, to be fair, she hasn't read the blurb.
UkiahOregon's realization that he's an alien (actually a Half-Human Hybrid, but he doesn't know that yet) is rather traumatic for him, especially since he now has to explain this to his brand-new girlfriend.
Pact follows Blake Thorburn and his Distaff Counterpart Rose Thorburn, who is an artificially created vestige trapped in a mirror world. After Blake has his connections to the world eaten by a demon, however, Rose steps into the real world, assuming his place amidst his family and friends. Blake eventually realizes that this means that he, not Rose, is artificial, created so that Rose, protected in her mirror world, would have someone to take the blows for her as she was initiated into the secret family practices, and that correspondingly everything about his past was calculated in order to make him avoid physical contact, which made him decay, while simultaneously being someone that would do everything in his power to help Rose, a family member trapped in a terrible situation.
"The Tale Of The Thirteenth Floor''. The adopted Karin is invited to The Little Shop That Wasn't There Yesterday on the 13th floor of the apartment building. The employees are soon revealed to actually be aliens with three fingers and no faces, and seem to be trying to abduct her. After she and Billy escape, and the ship leaves, Olga reveals to Karin through the TV that the aliens left her there ten years ago and were trying to rescue her. Billy then looks at her and sees that she has shapeshifted back into a faceless alien as well.
The Tale of the Dream Girl. Johnny, after putting on a girl's ring, is being pursued romantically by the ghost of the ring's owner. The girl in question has a backstory and death similar to that of the song Teen Angel, where she ran back into a car that's dead on the train tracks to get her ring when the train hit. Johnny eventually realizes that he was in the car with her (and her boyfriend). He ran back to pull her away but he didn't make it and died with her.
This is why his sister is the only person who can see him and why his mother ignores him, why their boss looks guilty after NOT needing a mechanic due to Johnny's work and why his sister gives him a funny look when he tells her no he can't calm down, how would she act if she saw a ghost.
Another episode had a girl thinking the new neighbour was a ghost, only to learn she was the one who was dead.
Another girl wanted know about the story of a ghost car that appeared every year at the corner of the ceremony. Her two new friends helped figure out microfilm and learn the sad story of the young man wanting to meet his date who was tragically lost. Now the girl knows the story she can reveal she is the ghost the car is waiting for and goes to meet the driver.
Bizarrely enough, the Mind Screw ending of The Prisoner implies that this is the entire premise of the series.
In the episode The Schizoid Man, Number Six seems to have been mistaken for an agent trained to impersonate him. Evidence mounts that in fact he is the impostor, and has forgotten his own identity. But in the end, the trope is subverted as he realizes that's what they want him to think.
"Tin Man" (season 1): The SG-1 team seems to have been transferred into robot bodies by a lonely alien maintenance man. In the end, they find out that they weren't transferred, they were copied, with the originals still alive.
"Fragile Balance" (season 7): Jack O'Neill wakes up after an alien abduction to find himself in a body 30 years younger... and slowly dying. After convincing his colleagues of his identity and tracking down his abductor, he finds that he is actually a genetically damaged clone of the original O'Neill (still with the alien).
In "Michael" (Season 2), Lieutenant Michael Kenmore awakens in Atlantis' infirmary, unable to remember who he is. After being informed of who he is and that he barely survived terrible injuries from a raid deep in enemy territory, he is let out and undergoes psychiatric therapy (including periodic drug injections) for the strange nightmares he keeps having. He eventually discovers secret observation videos of himself in the infirmary, and is horrified to discover that he is actually a Wraith that was transformed into a human using an experimental genetic drug and then brainwashed.
In "This Mortal Coil" (Season 4), Sheppard, McKay, Ronon, Teyla, and, later, Dr. Weir find that they are replicator-made copies of themselves, and that the version of Atlantis they are in is also a copy. They come to take it remarkably well, especially McKay. Mostly because of McKay's insight into the situation.
In "The Kindred" (Season 4), Carson Beckett is found by the Team. The only problem: he's supposed to be dead. But he insists and is sure, that he is the real Beckett. Turns out he is a clone.
Happened in the original Star Trek episode "What Are Little Girls Made Of?" with Nurse Chapel's lost boyfriend.note In this case, the boyfriend knew all along that he's an android body containing the human's memories. What he doesn't realize until the end is that he's not "the same person", as demonstrated by his amoral and insane actions over the course of the episode.
And with Rayna in "Requiem For Methuselah"
Also happens to Kirk in "The Paradise Syndrome".
Behold the god who bleeds!
Happens to a damaged, amnesiac Data in Star Trek: The Next Generation episode Thine Own Self when Data takes up a life in a pre-industrial village. The reveal is obviously not a shock to the audience, but a big one to Data.
The TNG episode Eye of the Beholder plays with this trope in all sorts of ways. It turned out that telepath who had died during Enterprise's construction had left a sort of 'psychic residue' which had imposed the dead woman's memories on empathic crew members unfortunate enough to wander into its proximity (it had caused one such crewman to commit suicide). Troi at one point actually screams in horror when she doesn't recognize her own reflection.
Star Trek: Deep Space Nine, "Whispers": We follow Miles O'Brien in flashback form as he seems to combat a station-wide conspiracy to sabotage peace talks amongst two alien factions; turns out the O'Brien we're watching was actually a "replicant", sent by one of the alien factions and programmed to assassinate the leaders of the other faction. But the replicant O'Brien was too perfect and ended up acting just as the real one would.
Also in the episode "Second Skin," Kira is kidnapped by the Cardassian Obsidian Order as part of an anti-dissident setup and told she is actually Iliana Ghemor, a spy, who was implanted with false memories so even she would believe her cover story, sent to infiltrate the Bajoran resistance subverted in that she is NOT Iliana Ghemor, but Iliana is a real person, who really did have false memories implanted so she could infiltrate the Bajoran resistance. It's all part of a trap to reveal that Iliana's father is part of the dissident movement as he decides to smuggle her off Cardassia when Kira's reaction is disbelief.
Voyager did this with "Course: Oblivion", where the entire crew realized that they were in fact not the real Voyager crew. (About halfway through the episode, which is rare for this trope. Usually it's a twist ending, not a twist middle.) Several episodes earlier, a semi-sentient, planet-spanning, not-quite-lifeform on an inhospitable planet they visited to refill on deuterium (you know, that stuff you can make from water and exists everywhere) had replicated the entire crew. Unbeknownst to the original crew, they eventually copied the entire ship, too, right down to the last bulkhead (try not to think about just how they did that). They forgot they were copies and made warp drive modifications that were harmful to themselves, so they raced back to Voyager hoping to get more genetic samples to save themselves. They failed to get back before disintegrating completely, dissipating just before they could contact Voyager.
It was even more bitter than that. Eventually, they gave up hope of their own survival and were merely trying to pass on the new technology (that was going to get them home very, very quickly) to their originals. They very nearly succeeded.
The Twilight Zone, "After Hours": Marcia White's shopping trip to a department store goes awry, as the people she talks to seem to transform into mannequins. In the end, we find out that she is a mannequin, whose month posing as a human is up. Also used in the '80s remake.
Also the episode "Four O'Clock": A self-righteous man goes around telling anyone who will listen that at precisely four o'clock he will, by sheer force of will, cause every evil person on the planet Earth to shrink to two feet tall. Four o'clock rolls around and the man finds himself shrunk to a height of two feet tall, much to his chagrin.
"In His Image", after murdering a woman on the subway platform, Alan Talbot returns to his home town with his fiance, but discovers that nothing is the way he remembers it. Then he discovers that he is really a robot created 8 days prior, and all his memories were a fiction of his creator Walter Ryder, who wanted to build a more perfect version of himself.
"Five Characters in Search of an Exit" is also an example. A clown, a hobo a dancer, a bagpiper and a major wake in a prison with smooth walls and an open top. They speculate for a long time about where they could be and at one point the major calls the place "Hell" but at the end it is revealed that they're all toys that are to be donated to the less fortunate children during the Christmas season. Their prison is a donation bin.
The new Battlestar Galactica has done this with five characters. Boomer spends the first season wrestling with the slow realization that she's the Tomato in the Mirror. Moreover, as of the Season Three finale, Tory Foster, Galen Tyrol, Sam Anders, and Saul Tigh are "triggered", and realise they're Cylons.
Boomer literally has a bad experience with her locker mirror, on which someone (herself? - even her Cylon personality isn't sure) has written the word CYLON in big yellow letters.
And in the series finale Head!Baltar and Head!6 explain in the final scene set hundreds of thousands of years later that Mitochondiral Eve is actually Hera (the Human/Cylon infant that both sides have been desperately trying to protect or kill) thus making Us the descendants of three species: the Cylons, the "Alien" humans and the "Native" Humans. WE ARE THE TOMATOES!
In one episode of Quantum Leap, Sam finds himself in the body of someone in a mansion where everyone thinks there's a vampire on the loose. After clearing up the situation, he finally gets around to looking in a mirror... and doesn't reflect. Literal Tomato "in the Mirror." This was hinted in the end of the previous episode, where we see the character Sam switched with actually had vampire fangs (played by Robert MacKenzie, who bears a close resemblance to Christopher Lee).
The climax of the Doctor Who episode "Utopia" revolves round the revelation that the kindly human Professor Yana is, unbeknownst to him, the Tomato in the Mirror, a 'sleeper' personality and biological disguise created by the Doctor's archenemy the Master, previously thought dead. His original personality and biology is contained, thanks to some Applied Phlebotinum, in a pocket watch, and released when Yana is tempted into opening the watch.
Before this we have the Doctor himself turned into a human teacher in 1913, through use of this pocket-watch-device. Of course the viewer knows who he really is, but the Doctor doesn't and once he finds out he's pretty shocked and doesn't want to go back.
In The Next Doctor the Doctor finds another person who claims to be the Doctor, who he takes to be a future version of himself. This other Doctor is investigating the place of a guy who died. It turns out the new "Doctor" is the guy that supposedly died - he'd had info about the Doctor overwritten over his mind.
Turn Left's time-beetle on Donna's back counts, considering that, while the audience knew about it, Donna didn't, and anyone who stared at her back, knowing something invisible was there, was instantly met with Donna telling them off for acting so strange, only for her to find out there was something (horrifying, too) there.
In The Pandorica Opens we get Rory and the Roman Legion, who are actually Autons.
At the end of the episode, the Doctor discovers that an alliance of all his historical opponents has joined forces to fight and imprison what they consider to be the most dangerous, monstrous and terrifying being to ever exist: him.
In The Almost People, we have Amy, who is in fact a Ganger, with the real Amy in a medical-looking tube thing, and about to give birth.
Doctor Edwin Bracewell in Victory of the Daleks believes he is an allied scientist who created a new form of unmanned weapon. He is actually a bombed android created by the Daleks as part of their cover.
Bracewell: But I created you! Dalek: No. It is we who created you!
In Asylum of the Daleks, Oswin Oswald helps the Doctor from her crashed escape pod. When he finally reaches her, it turns out the Daleks had captured and converted her into a Dalek long ago. Her human body and escape pod were a delusion she used to forget what had happened.
We now know that this version of Clara Oswald was in fact just a copy of Clara, created by the real one specifically to be in place to save his life. The copy herself was unaware of this.
In Journey To The Centre Of The TARDIS, there is a subversion in Tricky, who is told by his superiors that he's a robot but after he is proven to feel pain the Doctor knows he is not only human but the superiors' youngest biological brother. The brothers told him he was a robot after suffering a traumatic injury to gaslight him and get away with abusing him.
In Power Rangers Turbo: Justin notes that the other Rangers are acting odd, and finds out that they are really robots. At the end of the episode, it's revealed that Justin himself was a robot, who was programmed so that he didn't know he was a robot, and that the real Ranger team built them to help Zordon on Eltar. Lot of good that did...
The Torchwood episode "Sleeper" has a seemingly human woman with a seemingly happy life (complete with job and husband) find out that she's actually an alien who will be "triggered" to wage a campaign of terror on Earth.
In an episode of Sliders, the world is populated by almost entirely by androids, and one human scientist who attempts to create an android with the transplanted memories of Quinn. It turns out that the scientist actually died, and his memories have been transplanted into an android version of himself, without him actually knowing that.
As with many, MANY episodes of Sliders, this is a Shout-Out to a classic, in this case the film The Creation Of The Humanoids.
The core premise of Invasion. Set in a small Florida coastal town, several characters return from unremembered experiences in the water feeling not quite themselves. At first they appear to have been altered by mysterious glowing creatures, who may or may not be aliens, in the water. But it's soon revealed that they are in fact altered copies, and their originals were killed in the duplication process. Since they have the same memories, emotions, and personality as their originals, it raises the issue of whether and why they should be considered a different person at all. Each of them, and their 'unaltered' friends and family, answers the question a little differently.
Sadly, the series was canceled after one season, so this was never resolved.
Angel: in "Spin the Bottle", everyone's memory is wiped back to age 17. Wesley, who at that age was head of his class at vampire-hunting school, reckons it's a test: they've been locked in this abandoned building with a vampire, whom they must identify and kill. Angel (who at that age was a living human), in a private moment, looks at a mirror ...
Supernatural: In "Road Kill", the Monster of the Week doesn't know she actually is dead (and thus, a spirit haunting a stretch of highway) until the end of the episode.
The Monster of the Week in "Heart" has no memory of her transformations into a werewolf, so she doesn't truly realize what she is until Sam traps her in her apartment and she awakens to see how she's torn the place up.
Red Dwarf: This trope is played with in the episode Out of Time, when Lister is apparently revealed to be a Ridiculously Human Robot. He is floored by the revelation, but gets no sympathy from Kryten, who points out that his emotions are only artificial. However, the moment the crew escapes the unreality pocket through which they were traveling at the time, he becomes human again. (In fact, as the other reality was false, he had never been anything but human.)
Rimmer in various episodes. In The Inquisitor, a copy of himself provides a Reason I Suck Speech; in Terrorform, it's through a speech delivered by a living version of his self-loathing; and in Rimmerworld he is marooned on a planet with only his clones for company.
In the episode "Omega" of Dollhouse we find out that Dr. Saunders is actually a former Doll, Whiskey.
Later, after seeing Senator Daniel Perrin investigating and campaigning into the Dollhouse, we find that Perrin's wife is his handler, and he himself is a Doll. The whole purpose of his zealous investigation into Rossum Corporation's mind-wiping activities is so that he can discover evidence exonerating them at the end and place them above suspicion.
Played for Laughs in a scene where a programmed Sierra (played by Dichen Lachman who is ethnic Tibetan on her mother's side) doesn't want to get her treatment from Ivy because "I'm not comfortable with, uh, orientals."
The Fear Itself episode "New Year's Day". A young woman wakes up during a Zombie Apocalypse and tries to get to her friend's apartment. At episode's end, it's revealed she committed suicide the previous night and is now one of the zombies.
The Buffybot, in her premier in the episode "Intervention". Not only did she think that the real Buffy looked like her, but so did everyone else.
Also parodied, in that the Buffybot is quite overtly a heavily Flanderized version of Buffy herself; Buffy is, not entirely surprisingly or unreasonably, a bit pissed that her friends were completely unable to tell the difference. Especially since "s/he's a robot" as an immediate explanation for the Monster of the Week was almost a Running Gag for the season up to that point — and everyone pegged April as a robot just a few episodes earlier.
Dawn's among the last to learn that she's only six months old.
A long sequence in "The Replacement" follows "real" Xander watching Xander doing various errands and "hypnotizing" people. This convinces the "real" Xander (and the viewers) that the other Xander is a robot or demon. Eventually, "real" Xander discovers that he is Xander's weaker points, and the other Xander is Xander's stronger points. The coin he's using to "hypnotize" is merely a nickel he found squashed by a train that he plays with in idle moments.
Kamen Rider loves this trope. Usually, the monsters in the show have human guises (or in the case of one show,were humans), and usually, one of the main riders is a monster as well. Some examples include;
In one episode of Alfred Hitchcock Presents, a man goes to a psychiatrist because he's begun having delusions that he used to be a Martian. It turns out, he is a Martian, and is merely one of thousands of invaders. Fortunately, the psychiatrist is also one, and he's able to silence him before he can blow their cover.
Played for laughs in Chappelle's Show, which had a sketch featuring a rabid member of the KKK who's blind so he doesn't realize that he's black.
In the American version of Being Human, Sally Malick is first hunted by a ghost calling himself the Reaper, who claims that it is his duty to destroy ghosts who, like Sally, have stayed on earth too long or who have become destructive in some way. Then the Reaper starts trying to recruit Sally to become a Reaper, and then starts destroying innocent ghosts, increasingly seeming like a psychopathic serial killer. Yet, for some reason, everyone seems to be blaming Sally for the killings, even though she is desperately trying to stop the Reaper. Until the reveal that she isthe Reaper.
In an episode of Once Upon a Time we follow the story of Red Riding Hood, whose grandmother is trying desperately to keep from seeing her boyfriend at night. Red becomes convinced that he is the Big Bad Wolf that is terrorizing the town, when it is actually Red herself that's the werewolf, inherited from her mother, and Granny was trying to save the boyfriend's life.
The big awakening at the end of season one could be considered this trope for most of Storybrooke.
One episode of 3rd Rock From The Sun has Harry suffer a blow to the head, resulting in amnesia. The result is that he becomes alarmed that his family are aliens without realizing he is one as well. Crosses over into Dramatic Irony.
Emma Thompson: You know the word "luvvie"? Stephen Fry: Yeah? Emma: What do you all feel about it? Stephen:[sigh] I mean, I'm not going to get as upset as some actors do — some actors say, "We do a bloody hard job of work, we're serious people, you know, it's a coal face, doing a play! How dare they call us luvvies!" I think that's a bit overdone. On the other hand, it's a bit tedious when the Daily Mail says "luvvie couple XYZ," or something.... Emma: Do you know what the first citation of it is in the OED? Stephen: No. Emma: It's you. [cue My God, What Have I Done? reaction from Stephen]
The Arrested Development episode "Marta Complex" has Gob overhear a phone conversation Marta has with her mother where she says she no longer loves Gob and is in love with "Hermano". Gob asks Michael to find Hermano for him. At the end of the episode, Michael discovers that Hermano is Spanish for "brother". Marta was telling her mother that she was in love with Michael, Gob's brother.
Weirdly inverted by The Muppets in the "Secrets of the Muppets" episode of the Jim Henson Hour. You'd think the revelation that they are only puppets would shock the Muppets, but in fact they already know about it, and just find it intensely creepy (they avoid looking down and call anyone who uses "the P word" a traitor). But at the end they look and and realize "There's nothing but floor down there!". Apparently they are real, which turns the rest of the episode into a bit of a Mind Screw.
In the final episode of the short-lived series, "Do No Harm" Jason, who has spent the entire series trying to rid himself of his dubiously moral second persona, Ian- supposedly his long-dead twin brother- learns that, in fact, young Ian killed young Jason. HE is the double, invented by Ian. Worse, he learns this just as the doctor he thinks will be destroying Ian, but who has actually double-crossed him, injects him/Ian with a chip that will eliminate him forever. Cue "Goodbye Jason" and the end of the series.
Hang on, John! We're out of this at last Something's changed, it's not your face It's mine!
Who Will Love Me Now? by PJ Harvey is a narrative song where the character sings of monster in the forest who has done terrible things, the monster lamenting 'who will love me now?' At the end of the song the character reveals they are the monster.
This is played with in The Emptiness, by Alesana. Specifically, The artist and the thespian are one in the same.
The video for Garbage's "Bleed Like Me". Shirley Manson plays a nurse in a mental hospital; she eventually realizes that she's actually one of the patients.
Sally Fingerett's song "She Won't Be Walking" is a song about domestic abuse. The chorus is positive and hopeful:
She won't be walking, when she goes Won't be talking; they'll be nothing they don't already know Are no magic words left to say She'll be leaving him, flying away
Then you find out that the reason she'll be flying instead of walking is because she's a ghost. Her husband shoots her in the last verse.
Arkham Horror has an expansion that adds Tomato in the Mirror as a mechanic. Roaming Innsmouth runs the risk of drawing Innsmouth Look cards and learning your investigator is a Half-Human Hybrid, mimicking the Lovecraft examples under Literature.
This is a huge element of the fetches in Changeling: The Lost. They believe themselves to be ordinary humans, but they have the ability to see things others can't — that is, the people on the street who look like monsters. At some point, the fetch usually finds out that it's not a real person; it's a copy made by one of The Fair Folk to serve as a replacement for the human they took to Faerie to serve as their plaything. Those "monsters" they're seeing? They're the people who managed to escape from Faerie in the first place. And a lot of them aren't big fans of something fake living their life...
The Changeling book also suggests this motif as a brilliant Twist Ending Prelude: the players start going through life, noticing really weird things, scary critters just outside of the reach of their perception. Surprise! All the players are fetches, and the "evil creatures" are their real, changeling selves, come to finish them off.
Werewolf: The Forsaken also has an element of this. What's that? You're just an ordinary person being stalked by werewolves, spirits and ghosts? No, you are a werewolf, and you always were one since birth - it's just been dormant. (The bite is so that they can track you down after you go through your violent First Change - it's not infectious, and the Change proceeds with or without the bite. A panic-stricken person post-Change might not realize this or be in the mood to listen to the explanation, so consumed with fear over being a "monster"...)
In Clue the winning player may discover that they are the one who killed Mr. Boddy, forcing them to declare that they killed Mr. Boddy - and can still lose if they get how and where wrong.
Mimicking HP Lovecraft's own writing, this sort of reveal may on occasion be sprung on player characters in Call of Cthulhu scenarios, including several published ones — at least one of which gives the GM staging tips on when and how to secretly replace the original human characters with initially unaware dopplegangers in such a fashion as to keep even the players running them at the time ignorant of the switch.
One of the earliest examples in video games is Final Fantasy VII: Cloud, the protagonist, suffers from freaky headaches and weird disjointed flashbacks. It then transpires that he is a clone of the villain, Sephiroth, and has been acting under Sephiroth's Mind Control for the game so far. Even more confusingly, when he recovers from his Heroic BSOD, he realizes he was never a clone to begin with (what he really is, is quite complicated, but it involves the way the Super Soldiers are created, and how The Virus contains the genetic memories of those infected). Then a big reveal occurs where it is eventually revealed that much of his memories were not his own, but were in fact partly borrowed from that of his dead best friend Zack. When he finally regains his true memories, he finally develops into a fully fledged person.
The term "Clone" is a misnomer. In the original Japanese script, they were known as Sephiroth Copies, not clones. They're not genetic copies, but rather people who were rounded up after the Neblihiem incident and injected with a shit-ton of Mako Energy and Jenova cells as part of an experiment.
Same thing applies to the Sephiroth you keep following around, who turned out to be a more literal clone of the real Sephiroth who actually died after the events in Nibelheim.
Metal Gear Solid: Solid Snake goes into Shadow Moses Island to rescue two hostages, and stop terrorist leader Liquid Snake from launching a nuclear strike. The hostages he's meant to rescue keep having heart attacks, and Meryl claims he looks just like Liquid. Snake then discovers that both he and Liquid are clones of Big Boss, and that he's been used as a vector for the FOXDIE assassination virus.
Liquid has a second later of ketchupy goodness rendering himself a double tomato, though he never finds out personally. He knows he's a clone, but thinks that he's the inferior genetic specimen while Solid got all the good gene goo in the course of their creation.
If anything, Raiden in Sons of Liberty is an even bigger tomato than Snake. A former Child Soldier who suppresses his traumatic memories, he goes through all kinds of virtual reality training reenactments of Snake's best missions, and his mission in the Big Shell was modelled right off of the Shadow Moses mission. His relationship to the game's Big Bad, Solidus Snake, closely resembles the one between Solid Snake and Big Boss, and the entire mission was meant to be an experiment to transform Raiden into the spitting image of Solid Snake himself as well as a social experiment in giving The Patriots control over all digital information. To say that Raiden was an Unwitting Pawn by this point would be a grand understatement.
The Force Unleashed II is all about Galen Marek aka Starkiller trying to find out whether or not he's the original Starkiller or a clone. Turns out he never does get an answer.
Killer7: Thought the Killer 7 were Harman's split personalities? Nope. They're Garcian's.
The last level of Braid has Tim running a deadly gauntlet, with the Princess following above, disabling traps and opening doors. He reaches the end and rewinds time, revealing the truth: she was setting traps and closing doors, trying to keep him away.
In the extra stories the player can follow when they go into levels and get to the end of the game reveals that the woman in the stories (or the princess) is a metaphor for the atomic bomb.
In Klonoa 1, Klonoa himself turns out to be from an alternate reality at the end.
In the true route in Ever17, the amnesiac Kid looks himself in a mirror and realizes that he is not the same Kid seen in Takeshi's perspective. In fact, he isn't even the Kid he sees in the mirror. He is the reader.
In the flash game "Trapped" you believe you are Benjamin Greunbaum, the owner of the hotel you're in which is under siege by a group of robbers. This impression is based on finding a wallet with that name in it. Turns out, you're actually Dan Mcneally, the guy in charge of the robbers, hit with a sudden and unexplained case of amnesia. Greunbaum is in the ventilation shaft... well, his body anyway.
The sequel "Escape" has Dialla told that she was once the leader of the Armored Gamses, the very gang she and her partner were trying to take down. Also she and Dan were a couple.
In the original Japanese version of Street Fighter 2010 (not the American localization that claims the protagonist is Ken Masters), Kevin Straker is one of the very "Parasites" he was sent to destroy. It was all part of Dr. Jose's master plan to use him to conquer the universe...which promptly fails when Kevin kills him.
Clone Zero is the real Zero, his "heart and soul" transferred to the clone body. Omega, original body or not, is one entirely different person.
Mega Man X: The heart is what counts. Not the body...
This is echoed in Mega Man ZX Advent. Grey has spent enough time fighting for his life against Maverick Mechaniloids, Pseudoroids, five other Mega Men, and both Prometheus and Pandora that when he finally learned that he is actually Master Albert's backup body and Model A a recording of his data and powers, he stopped giving a damn about who he originally was. That one of the Mega Men in question was Aile certainly helped him stop caring about his predetermined identity.
In Final Fantasy X, Tidus discovers that he and his civilization don't really exist. They did exist at one point, but they were obliterated in a war with Bevelle. Now they're just all part of a dream being generated by the survivors of that civilization, which are now a gestalt of magical naked people trapped in a mountainside. No. Really.
Hell NightThe player turns out to be the Dark Messiah, not only explaining why they were chased by the Cult, but also the kidnappings. And why the train was wrecked by the monster.
In Super Dangan Ronpa 2, no one could have predicted that the cast was really former members of the terrorist organization Super High School Level Despair, least of all Hinata Hajime, the protagonist who is merely a reconstruction of pre-surgery Izuru Kamukura, Super High School Level Hope. Talentless? Not even close.
In Kingdom Hearts II, Roxas starts seeing mysterious people that no one else seems to notice. He eventually discovers that the Twilight Town he's been living in is a fabrication, and that he himself is a "Nobody" of the main character, Sora.
The Minerva's Den DLC from BioShock 2 ends with Alpha Series Sigma discovering that he is really Porter, who had been framed by Wahl and sent to Persephone, and the "Porter" who had been helping him was really the Thinker.
BioShock Infinite utilizes this trope as well, considering that Comstock is really Booker DeWitt from an alternate timeline where he was baptized after the Battle of Wounded Knee and began his descent into darkness.
The short interactive fiction 9:05 revolves around this concept. Hints to your real identity include the lack of a stereo or TV in the main room, and the broken lock on the front door. It turns out this isn't your house, that isn't your boss on the phone, and you stashed Hadley's body under the bed.
City of Villains has a story arc where the player character uncovers clues that they are in fact robotic duplicates made by Nemesis. Subverted by the final mission, which explicitly states that the player character is the original, but the contact who sent them on the missions is the robotic duplicate (with the real one alive but captive).
Even before that, there was Kain's dilemma: Originally lead to believe that by killing the mythic Circle of Nine he could be released from his vampyric unlife, he eventually learns that he is, in fact, one of its members, the reincarnated guardian of the Pillar of Balance, and his liberation from vampirism may only come in death.
Gets better. In Defiance, Raziel rips out Kain's heart, saying "I have found the Heart of Darkness!". Janos' heart, which was pulled from the vampire by Sarafan Raziel, was inside Kain all along. Kain was unaware of this fact.
In Luminous Arc 3 Levi discovered that he is the clone of the man antagonist, the God but is said by his companion that the thing that matter is [[spoiler:Levi's heart is human.
Subverted in Deus Ex, in which protagonist JC Denton is informed that both he and his "brother" are actually artificial life forms. Rather than reacting with shock, angst, or an unconvincing identity crisis, JC calmly takes the revelation into stride, and remarks that he had considered the possibility in the past. His artificially constructed memories of the past, that is.
One of the few discrepancies in Deus Ex is JC's history. In one version he was cloned and artificially aged, being about six months to a year old during the game. In the other, he was genetically engineered but was raised in Switzerland. Both of these versions are supported by information from characters who knew The Truth in the form of email archives, statements, and physical evidence within The Conspiracy. In the final area, JC first guns down the man who killed his father, then sees his cloning tank, and the one that is growing his younger sibling, Alex D. To address these issues the DX team created the Deus Ex Continuity Bible with the issue at hand explained here. Needless to say, the site contains massive spoilers.
In Team Dark's ending in Sonic Heroes, Rouge discovers hundreds upon hundreds of copies of Shadow in tubes identical to the one he was in at the start of the game. It matters little, though — once he's over the shock, he decides that original or not, he's still the Shadow the Hedgehog. This is followed up on in one of the multiple endings of Shadow the Hedgehog, with Eggman admitting that Shadow is one of the copies. He gets over it instantly, kills Eggman and takes over the world.
In the canon ending of Shadow the Hedgehog, Eggman tells Shadow he is the original, and he found him after he fell to earth and put him into a capsule to let him heal.
The canon ending also has a completely separate Tomato in the Mirror twist: Shadow was created from Black Doom's blood, making him at least partially a Black Arm.
The World Ends with You pulls this twice: first you find out everyone playing the Reapers' Game is dead and trying for a new chance at life, and then it turns out that Shiki traded her appearance to play the game, and always appeared as her friend Eri.
Joshua. He killed you. No he didn't, Sho did. No wait, yes, he killed you so that you could be his proxy for the game. And he's God. This is after the sudden revelation that Joshua has been alive the whole time.
In Max Payne 2 The Fall Of Max Payne, the show within a gameAddress Unknown ends like this: The protagonist, John Mirra, who spent the entire show looking for the murderers of his family, realizes that he himself was the killer after he sees the killer's face staring back at him in a bathroom mirror. This, incidentally, may mean the whole purpose of the show was to set up a truly terrible pun: the main character is named John Mirra, and he solves the mystery in the bathroom (as in, the john) by looking into the mirror....
In Xenogears when Fei finds out that his father is really the new body of Grahf, and also Wiseman is his father as well.
Not only that, but he also discovers that he is the omnicidalmaniac ID, while his current amnesiac personality was artificially made after he committed a genocide. Then he discovers or should we say remember that he became crazy because his mother was Miang and made a lot of gruesome and painful experiments on him Then, we learn that Grahf and Fei are actually the same person, in two different bodies, and that 500 years ago, he was the lover of the game's world equivalant of the pope who made a Heroic Sacrifice for him, causing Lacan (Fei's name at the time) to become the immortal Grahf while his original personality kept reincarnating. If this was not enough, Fei later learns that he is the ancestor of every inhabitant of the world, which he was not supposed to be, that free will exists thanks to him, and that he created his soul mate 10.000 years ago as a child because he felt a need of protection while he was linked to The Wave Existence, which gave him the power to wish his feelings into reality, and that all of it makes him basically the The Antichrist, except that here, the Antichrist is the ''good'' guy. Fei is not a case of Tomato in the Mirror, he is The tomato, the mirror, the frame of the mirror, the room in which the tomato and the mirror are, and the architect of all of this actually wants to be killed by him
In Wild ARMs 1, Rudy has his arm severed and when his friends try to heal him they discover that he is not human, but an artificial life form created as a weapon, and his body is biologically similar to the demons they are fighting.
Something similar happens to Jet of Wild ARMs 3 when he finds out he is not actually Dr. Enduro's son, but actually an Artificial Human created to interface with the Yggdrasil System.
In Castlevania: Aria of Sorrow Dracula is Killed Off for Real before the start of the game. Its main villain claims to be Dracula's reincarnation. He's not, the mysterious power possessed by the main character, Soma Cruz is Dracula's power, and Soma is Dracula reincarnated. Cue Enemy Within.
As if Konami can't stop recycling the plot enough, a similar theme appears in Neo Contra when protagonist Bill Rizer meet with the "real" Bill Rizer, A.K.A. Master Contra. The Big Bad reveals that both of you were part of a program called "Project C" in an effort to stop global warfare, and thus was cloned from the concious of a legendary soldier. Considering how the game pokes fun at the Contra series and its sillier bits, it is probably an intentional jab at That Other Series From Konami.
S.T.A.L.K.E.R. Shadow of Chernobyl: You wake up at the start of the game with no memories and a single note in your PDA saying "Kill Strelok. Turns out you were captured and brainwashed by C-Consciousness and given the objective to kill Strelok, C-Consciousness having thought you had actually escaped when your original foray into the power plant failed.You were Strelok all along This turns out to be an odd example of the antagonists being brought down (at least, if you pick that ending) by their own competence.
Ys Book I and II: Feena first appears in Book I as a ordinary-looking girl locked up in the Shrine dungeon, and seems to have lost her memory. In Book II, right before the final boss, she is revealed to be one of the twin goddesses of Ys. During the ending cutscene, she tells Adol to "remember the girl in me".
Snatcher pulls this off rather beautifully. So, Gillian Seed is a DeckardExpy working for an organization hunting down Snatchers, robots that look like humans. Also, you and your wife have amnesia and can't remember anything about your past. Well, it's quite obvious that You and your wife are amnesiac Snatchers Except... Actually, neither of you are. You invented the Snatchers 50 years ago and were cryogenically stored.Hideo Kojima is so good a writer even the Genre Savvy are left in surprise. There are about 5 other Tomato Surprises that are subverted in the very same game too.
In Folklore, your two protagonists are an amnesiac Mysterious Waif named Ellen and an Intrepid Reporter named Keats. Ellen naturally gets freaked out at first by the supernatural discoveries she makes, while Keats takes it all remarkably in stride, mostly because he dismisses a lot of it as unreal and simply plays along to get to the truth. Their being drawn to the same location and chain of events appears to be related only by the person who called them. In reality, Keats is a Halflife, ghost-like beings that the player has interacted with the entire game, which are created by the strong wish of a human - in this case, Ellen's childhood friend Herve, whose dying wish was to protect her. Keats looks human because his appearance is taken from a drawing Ellen made of what she thought Herve would look like when he grew up; he's a reporter only because Herve wanted to be one, and the magazine he writes for (which Herve was a fan of) went out of business in the late '80s. The "office" the player sees Keats in at the beginning of the game is in fact another realm in the Netherworld. And he's part of the story because the whole chain of events 17 years ago is what created him.
Tales of Symphonia: Dawn of the New World features Emil, a cowardly teen who is given the ability to channel incredible power from the dormant spirit Ratatosk in order to protect Marta, who seeks to awaken the spirit himself from the core she carries and restore his power. Over the course of the game, Emil's recollection of certain major events is spotty, and many people in his hometown of Palmacosta, from which he left six months prior, know his name but don't recognize his face, much to his annoyance. Eventually it comes to light that Emil has not been channeling Ratatosk's power; he himself is Ratatosk, and the moments when he gains power to fight are him using his true abilities. Contrary to everyone's belief, Ratatosk had been awake for months, but was incredibly weak. In order to hide his true identity as he recovered, he created a fake persona using the appearance of a boy he'd killed named Aster. The fake was designed to quickly fill in the gaps of its memory; during the mass murder in Palmacosta six months prior, a women named Lana, blinded by her injuries, mistook Ratatosk for her son, Emil, and so the false persona came to believe it was Emil. No one in Palmacosta recognizes him because while there was once an Emil Castagnier there, this one looks completely different. The real Emil is implied to be dead, murdered at the same time as his parents. Furthermore, the core Marta has is a fake, designed to make her a target for those who seek to kill Ratatosk before he regains his full power.
In Persona 2: Eternal Punishment, The Sumaru City in which Maya and company live in is one big mirror, the denizens of the city (except Tatsuya) are pretty much tomatoes. In the "real world" (what Joker calls "the Other Side"), Maya was killed with the Spear of Longinus in Innocent Sin by Maya Okamura, and in having that happen, the world is destroyed, with the exception of Sumaru City. Stricken with grief over her death, Tatsuya and his friends demanded Philemon to do something about it. Philemon agrees to bring her back, but in the alternate world where EP takes place, but with a price—everyone must forget Maya and the friendship they shared. Everyone gives up their memory, but during the process Tatsuya out and out refused to forget Maya and through sheer force of will he ends up in EP's Sumaru with all his memories intact, causing a paradox. The Maya in this world runs across him and feels a strange déjà vu vibe from him, as well as pain in her side, where she had been stabbed in Innocent Sin.
In Persona 4, Teddie realizes he was a Shadow all along. Unlike most examples, the main characters (save for said character) were not terribly surprised by this, and took it in-stride.
The extent to which this trope applies in Digital Devil Saga is certainly arguable, but it probably applies when Serph realizes that he was created as a virtual AI doll version of someone who was experimenting on one of his comrades when she was two years old. Oh, and his spirit's still around and affecting him.
Ihe Cybran Campaign of Supreme Commander. Dr. Brackman, creator of the Symbionts, calls all Symbionts "his children" and refers to the player as "my boy". The debriefing at the end of the campaign reveals that He's being literal about the son thing - you are his clone.
Tales of the Abyss gives us Luke fon Fabre, a spoiled rich kid who's been shut-in at his mansion for seven years until the start of the story due to a kidnapping incident which shocked him into losing his memory. He soon goes on to find out that he's supposed to be the the world's savior, and continues to give everyone grief about how special he is. Cue the traditional Tales series megatwist, where he discovers that he's suddenly become a mass murderer, his beloved sword instructor set him up, all his friends are tired of his crap and to top it all off, he's the clone of the REAL Luke fon Fabre, who's been spending the last seven years trying to stop Van by working on the inside.
Star Ocean Till The End Of Time: The entire universe that Fayt and everyone else inhabits is an MMORPG created for the amusement of 4D beings, called the Eternal Sphere. And the creator of the game has decreed that all "bad" data must be deleted as he felt that the Eternal Sphere's inhabitants have grown to be too sentient, with technology that almost matches that of the "real" 4D dimension.
Tomato-In-The-Mirror reveals have become a staple of Silent Hill games since Silent Hill 2, in which James realizes that he killed his wife.
Especially prevalent, and beautifully done, in Shattered Memories. The basic premise of the game centers on the main character Harry Mason searching for his lost daughter Cheryl after a car accident. The bulk of the game is a mix of exploration and action (in the form of running your ass off from the demented creatures chasing you,) with bouts of psychotherapy interposed between segments.The obvious conclusion (considering Harry can't seem to die) is that in the narrative of the game follows Harry recounting his traumatic experiences to his therapist. However, in the course of the adventure through the town, you eventually find yourself at the office of a psychologist, and you go inside to discover the therapy sessions were happening concurrently with the gameplay. The patient turns out to actually be Harry's daughter, who is now somewhere in her 20s, and the Harry Mason the player has been playing is simply a delusion in Cheryl's mind. As the game eloquently puts it, you're 'not even a ghost'. And depending on your interpretation, it's ambiguous as to whether everything in the game was in Cheryl's mind or if her delusions were simply being physically manifested in the real town.
Fatal Frame 2 has an example of this. The player is led to believe that Mayu is being driven by the town's local Ax-Crazy ghost to kill twin sister, playable character Mio in order to complete an gruesome ritual that (among other things) requires an elder twin to kill his/her younger sibling. The game goes out of its way to show Mayu as a possessed, malevolent force. In the penultimate chapter of the game,it is revealed that the town has an odd legend about twin birth order — instead of older/younger they have inferior/superior, respectively, and the superior twin always allows the inferior to be born first. Now Mio, and the player by proxy, is the murderer, something shown to be canon in the third game.
In Super Robot Wars: Endless Frontier it's revealed that Haken Browning is W00 a genetically engineered human made by a project which tried to create the perfect soldier. It causes some worries, but it's fairly short-term. He's in a group consisting of a smart-mouthed android with a split personality, a second android with cat-ears and like-wise split personality, a 2000+ year old pettanko oni princess, another princess who's as top-heavy as her sword and a chinese fox-spirit who cracks more sexually slanted jokes than you can shake a sword-cane at. And the other guy was in a group even crazier than this one.
Baten Kaitos Origins plays this in a really interesting and powerful manner: you're the tomato. Yes, you, the player...well, in a sense. That strange world that Sagi keeps getting sent to, where a bunch of people keep calling him Marno? That's you. You're actually playing the role of Marno's spirit, not a nameless Guardian Spirit...oh, and by the way, Marno is one-fifth of the Eldritch Abomination Malpercio. Yup, you're part of the dark god that helped ravage the world a millennium ago and is the final boss of the first, chronologically-second, Baten Kaitos. Don't you feel special?
In Prototype, Alex Mercer had extremely mixed feelings when he discovered that he was the Blacklight Virus, while Alex Mercer was the person who released it on New York and was its first meal. Especially since the real Mercer was worse than the virus itself.
Alex Mercer:I'm not human. The revelation...it freed me. It killed me. I'm not human. *uneasy chuckle* Alex is just the role I play. Part of me was relieved...and part of me died. Just another disguise, right? So ingrained...so real...even I believe it.
Second Sight. It turns out that the main character isn't a lab escapee having flashbacks to a time just before it all went wrong, he's in that time and having precognitive visions on the verge of a Bad Future. One of the very few surprise twists where the character turns out to be himself.
In Disgaea 2, it is eventually revealed that Adell is actually a demon himself, even though he'll keep saying he's human.
Actually, Adell himself isn't told this in the main story, but it's pretty obvious to the player.
Disgaea 2 has another example Rozalin is actually the overlord Zenon, recinarting herself for fear of her own power
Phantom Dust has the amnesic main character searching for clues of his and everyone else's lost memories in the post-apocalyptic, ghoul-filled world. It is revealed to him by his friend, Edgar, that the protagonist, along with everyone else in the world save Edgar, are fabrications created by Edgar from the dust to help him overcome his loneliness when he returned from space to find Earth a complete, lifeless wasteland. When the protagonist beats the final boss it is further revealed that the Edgar you've known throughout the game is himself a fabrication, having been created by the original Edgar to watch over things after his death.
Phantasmagoria: A Puzzle of Flesh has this as its big endgame twist: Over the course of the game, the player character Curtis is haunted by insane visions, compounded with his own guilt over presumably causing his mother to hate him and eventually commit suicide, as various people he doesn't like around his office at Wyntech are being killed off. As Curtis investigates deeper into Wyntech's past, he discovers that the company used to dabble in experimenting with transdimensional portals, his father was involved in their projects, and Curtis himself was used as a guinea pig. The final reveal is that Curtis, who you've just spent the entire game playing as, is in fact an alien duplicate: The real Curtis never left the alien dimension, and has mutated and developed psychic powers to torment the clone Curtis with past dimensional barriers.
The big Tomato Surprise in Soul Nomad & the World Eaters revolves around the titular creatures - extradimensional entities cast between worlds by the various gods. The notable one out of them - and the one that applies to this trope the most - is Revya, a Drazilian shell injected with the soul of Median's dead son after 200 years of nurturing by Haephnes as her and Virtuous' part in the Gambit Pileup. Human!Layna gives you the breakdown once you cross over to Drazil proper.
Itsuki in Suika realizes that she is actually dead instead of her sister at the end of the first chapter.
Ghost Trick pulls a pretty major one in the end. Sissel spends the entire evening hunting down clues to who he was before his demise. At first, he assumes himself to be the blond man in the red suit seen on the game's cover. He spends the majority of the game using this persona until he discovers that the man in red is alive (kind of) and reverts back to a wisp. He all but gives up hope on finding his identity until the person whose face he was borrowing eventually reveals that Sissel was his cat. Major clues for this revelation include Sissel's limited understanding of human technology and complete inability to read.
the white chamber ends with the revelation that Sarah has murdered her entire crew. At this point, her ending fate is already sealed by in-game choices.
In a literal in-the-mirror moment at the end of The 7th Guest, Ego, the player character, is revealed to be Tad, the titular seventh guest.
In Arc The Lad: Twilight of the Spirits, Kharg discovers that he is a human/demos hybrid.
Baldur's Gate has the protagonist on the run, trying to figure out why everyone wants them dead. The discovery of a letter left by their adopted father reveals that they're a Bhaalspawn, a child of the Lord of Murder, and destined to rain destruction on the world.
This is reinforced (and in one case foreshadowed) when some of the Player Character's dreams has them looking in a reflective surface and seeing themselves with the same Black Eyes of Evil Bhaal had.
In the sequel, the protagonist's childhood friend Imoen is eventually revealed to be a Bhaalspawn as well. The shock of this and the torture she'd been under briefly breaks her mind and she temporarily becomes an Empty Shell.
Resident Evil 5: In a flashback set a few years before the events of the game, Albert Wesker discovers that he is just another one of Umbrella's old experiments — Project W.
Albert Wesker: Are you saying I was...manufactured?
One of the endings to Chrono Trigger that is only obtainable in a New Game+ leads to Marle discovering that she is now a descendant of Frog. She is not amused.
In Mass Effect 3 it's revealed in some old logs that took place before the second game, that Shepard was completely brain-dead when they were recovered by Cerberus, with one of the Lazarus Project scientists commenting that because of this, bringing Shepard back would be impossible. The fact that Shepard somehow was resurrected anyway, has them momentarily wonder aloud if s/he is the real one.
Shepard: Maybe I'm just some sort of high-tech VI who thinks s/he's Commander Shepard?
It's implied, that Shepard is the real one, but its never directly confirmed. Unless Liara accompanies you on that mission, in which case she responds to Shepard by saying that she knew Shepard was real the moment she met them in Mass Effect 2, and given the tactile telepathy that her species appears to have there's no reason to doubt her.
The "Citadel" DLC all but confirms that Shepard is real since Cerberus probably wouldn't have preferred a mere high-tech VI to their clone.
There's a easter egg alluding to this in the the first Mass Effect game: the layout of the Council's room, where they'd deny the existence of the Reapers, strongly resembles the outline of a typical Reaper ship.
King's Quest VI has a magic mirror in it that reveals someone's true identity. There are two places it can be used (though not in the same playthrough). One is in passing the Lord of the Dead's challenge to make him cry, wherein he realizes in an instant his long miserable existence. The other has Alexander revealing to his nearby allies that the supposed Princess Chasima is actually a genie in disguise.
In Virtue's Last Reward, the protagonist Sigma and 8 other strangers are abducted by someone named Zero and are forced to play the Nonary Game. Sigma, a 22-year-old college student, later finds out that he's actually 70 years old, an esper, has lost his eye, had his arms replaced by cybernetic ones, and is Zero. Needless to say, this is quite the shock to him.
In A Dark Room, you're a regular Featureless Protagonist. As the game progresses, you start to wonder why you can wield six or more weapons simultaneously, and why the entire military attacks you on sight... until it's revealed that "wanderer" means alien, and you and your ragtag bunch of villagers are what's left of an invasion fleet.
Evil Islands: It's eventually revealed that Zak's identity is that of the mysterious Joon you've been looking for during the Suslanger arc.
Fire Emblem Awakening has lovingly prepared a double-whammy special tomato puree surprise for you. You, as the Avatar, are Validar's child. Yes, the spawn of the madman who heads a Religion of Evil dedicated to the resident God of Evil, the Fell Dragon Grima; the same man who attempted to have your friends assassinated in cold blood in the middle of the night and the one who eventually forces you through magical thrall to attempt to murder your best friend (And quite possibly your husband, if your Avatar is female). That's the least of your worries. You are also the Magnum Opus of said Religion of Evil; have you ever wondered why your Avatar and your children are so stupidly strong? It's because you are the most perfect result of a Super Breeding Program designed to create a suitable vessel for said God of Evil, only your birth was so perfect that rather than create a person that hopefully would be good enough to hold the God, the god chose you to be his reincarnation.Youare the God of Evil. And Time Travel is involved in this game. And guess what? Nothing quite feels like a kick in the nuts like hearing the impending realization of your dark destiny coming from the mouth of yourself from a Bad Future where you willingly murdered your best friend/possible husband, ascended to godhood and proceeded to lay waste to the world, bringing unmeasureable death and destruction to all that lives and being basically single-handedly responsible for every single tragedy that's befallen the time-travelling children of your True Companions. YIKES. Fortunately for everyone not from the Grimleal, you can and WILL Screw Destiny to prevent the present from turning into that ruined future.
The three main characters in Phantasmat are all dead from drowning when a dam burst and flooded the town, although none of them initially realises it. The protagonist gradually reveals their pasts to them:
The girl: Convinced she was to marry her (philandering) lover in a secret wedding, she drowned while waiting for him in the church tower.
The hotel owner: A violent criminal who strangled the hotel's previous owner in order to 'retire' as the new owner. He drowned while attempting to hide stolen money by burying it.
The old woman: As the mayor's wife, she was envious of her husband's wealth and standing. She killed him by poisoning, then regretted it and drowned while mourning at his grave in the cemetery.
Continuing this, Phantasmat: Cruicible Peak has all people you meet that died in an avalanche that destroyed the town:
Greta: Got a call to skedaddle but gathered so many belongings and her car swerved on the icy road, slamming against a shop front and trapping her inside.
Peter: Died waiting for a letter from his divorced wife and kids and died at the post office.
Schultz: Was skiing down he mountains and died at the bottom of the hill when the avalanche hit.
Otto: A man who's had an...obsession with fire who would trigger a humongous explosion that not only created the avalanche but killing him with it.
In the Super NESSlayers game, Lina turns out to have been a duplicate for the entire game, while the real deal has been held hostage offscreen for most of it.
I Have No Mouth and I Must Scream: Nimdok is given the task to find "The Lost Tribe". He finds a mirror, that shows anyone with absolute objectivity, and learns a horrific truth. He sold his Jewish parents out to the Nazis to perform his gruesome experiments, and realizes he himself is the Lost Tribe.
Fans! had a short where Tim wakes up to find that he's the only person left on Earth. Two aliens offer him a series of female human clones modeled after people from his memories, so he can repopulate the world. The story ends with Tim finding out that 1) this is not earth 2) he's a clone too and 3) this was all the aliens' experiment to breed humans.
In The Order of the Stick, When the Order discovers Girard's gate, they find that all of the powerful sorcerers who are supposed to be guarding the gate are dead. While looking for clues as to what occurred to kill the mages, Vaarsuvius discovers that s/he killed them while performing the Familicide spell on the Black dragon that threatened to kill his/her mate and children. Que Heroic BSOD moment.
A Creepypasta story titled "Mice" featured a narrator who had trained "mice" into becoming intelligent and making their own communities. He regularly kills some of the weaker ones to discourage any rebellion against him. In the end, it's revealed that the narrator is actually a robot and the mice are really people.
Another Creepypasta relates the story of a kid being adopted into a family and the subsequent murder of his family members by an unknown man, except for himself, who turns out to be a dog.
Up until the Wham Episode in Red vs. Blue: Reconstruction, every problem that befell upon either the Red or Blue teams was caused by the Freelancers and their many AI. So naturally, it was a very shocking twist to find out that Private Leonard Church was actually the original Alpha AI that had been split into all the other AI that the cast had been fighting throughout the entire series. On top of that, the director of Project Freelancer is the real Leonard Church. Furthermore, as Revelations has since revealed, Tex is also an AI, based off someone the Director lost, but loved so much his memories of her spontaneously created a separate AI. Church preferred to believe that he was a ghost.
In Super Stories, the genius roboticist Veldron eventually learns that he's a robot duplicate of the real Veldron, designed to be an Expendable Clone.
The Darwins Soldiers story Card of Ten follows the tale of Dr. James Zanasiu and his team through the antimatter world of Gaman. At the end, it's revealed that this Dr. Zanasiu is actually an antimatter copy of the real one, who's still back on Earth.
"His Silicon Soul": A robot duplicate of Batman goes through this trope before his programming activates. The plan of the AI that created it is only foiled because the duplicate was programmed too well: it was programmed with all of the real Batman's personality traits, including his steadfast refusal to kill.
"Growing Pains": Clayface forms a separate sentient being, in the form of a young girl, to scout for him. She forgets who she is and is found by Robin who falls in love with her. She tells Robin of a man who is chasing her, and when they encounter him he seems to be her father; he tells the girl (Annie) that "It's time to come home." In the heartbreaking final scene, Annie realizes what she is, and throws herself into Clayface to save Robin, being absorbed in the process. Robin proceeds to leap right toward the Moral Event Horizon by hurling batarangs into the tank of industrial-strength solvent above them, causing streams to pour out onto Clayface as he demands he bring Annie back. Since Annie gaining separate sentience was a fluke to begin with, Clayface can't. Batman catches Robin's arm just as he's about to hurl the batarang that will execute Clayface.
"Judgment Day": Two-Face was targeted by a violent vigilante who called himself the Judge, and was determined to het him first. He and Batman were in agreement on this, as the Judge had already nearly killed both the Penguin and Killer Croc, and eventually, nearly succeeded in killing Two-Face by turning his own hideout into a Death Trap - going to so far as to seal off an escape route that Two-Face thought only he knew about - that Batman had to get them both out of. As it turned out the Judge was actually a third personality of Harvey Dent himself, created in response to his Two-Face persona in order to fight crime. As Batman said in the end. "That's why he knew about the escape route. He knew everything about Two-Face... Except that he was Two-Face.
The Batman, has Batman and Robin trying to distribute the cure for a madman's Zombie Apocalypse drug. Turns out they were the ones under the effects of a drug that gives you wild hallucinations about everyone else being a zombie, and that same hallucinogen was what they were about to spread through the entire city.
Used in an episode of Legion of Super Heroes. Superman relizes that he is actually the shape-shifting Ron-Karr, tricked into believing that he is Superman in order to be put to use as a spy.
And the only reason Ron-Karr was planted there was because Chameleon Boy(another shapeshifter) was planted in the villain's team with the same method, needing a similar Tomato in the Mirror moment to get him back.
Also from Justice League is the two-part episode Legends. After a few members of the League get transported to an alternate universe, they find themselves in a bizarre world that is seemingly a pastiche of the retro Golden Age and Silver Age comic books, with its own (cornball) version of the Justice League, the Justice Guild of America, who regularly battle against equally cornball villains. However, after some investigation by Green Lantern and Hawkgirl, it's revealed that the entire city was a Lotus-Eater Machine created by a Reality Warper, and the real Justice Guild died long ago trying (and failing) to prevent a nuclear war; in other words, the current Guild learns that they aren't even real. When Ray attacks and defeats the League members, the Justice Guild ultimately decides to fight Ray despite knowing that defeating him would result in a Dream Apocalypse that would take them with it. "We died once to save this Earth. And we can do it again."
Also Tyler in the episode "Inside Man", turning out to be a DNAlien who still is fighting it and trying to be human.
At the cliffhanger end of the Season Two finale of Transformers Animated, Sari looks down at her injured elbow to see circuitry poking out, and her adoptive dad, robotics genius Isaac Sumdac, responds "We need to talk." In the next season, it's revealed that Sari was a Cybertronian Protoform Isaac somehow came across, and sampled his DNA to create her form.
Except Isaac isn't her adoptive dad. He's the genuine article, even when you consider the revelation of Sari's "birth". After all, his DNA was required in order to bring her "online" and was what made her part-Human, effectively making her his biological daughter at the same time as being a robotic alien.
One of the "Scary Door" gags: "Why should I believe you? You're Hitler!"
In the episode "The Honking", Bender is run over by a "were-car" while staying at a mansion he inherited from his uncle. When people back in New New York are getting run over, Bender believes the were-car followed him, until it turns out Bender became a were-car himself.
Subverted in "Into The Wild Green Yonder". Fry looks around to find the person whose thoughts he can't read (the dark one). After not finding anyone, he concludes that he is himself the dark one, as his thoughts can't be read by other telepaths. However, the dark one is actually a small alien leech that Leela keeps nearby.
Played straight in Bender's Big Score though. Fry loses Leela to a man named Lars. He later travels to the past and splits in two, with the original Fry returning to the future and the time loop created copy staying and living 12 years in Fry's original time. When Bender travels back in time to kill this Fry, his attack burns Fry's hair off and damages his vocal cords, changing his voice. Time-loop Fry looks in the mirror and realizes that he is Lars and then travels to the future to court Leela.
In Rebirth an interesting variation occurs the first episode of the revived series. The Planet Express ship crashes after the events of the last movie, killing everyone, except the Professor and an amnesiac Fry, who is able to revive everyone with a stem cell machine. Leela remains in coma, so Fry builds a robot version of her in despair. The robot Leela learns of her true nature, but aside from some Angst, isn't concerned...until of course the real Leela wakes up, and they battle each other, so Fry is forced to shoot either one, and ends upshooting himself. Turns out Fry himself, was a robot, the real him was killed in the crash, while Leela, whom he shielded, survived. Since there was little left of Fry, Leela created a robot Fry. A malfunction, however, killed Leela forcing the Professor to use the rebirth machine on her along with the other dead crew members, and destroyed Robot Fry's memory. The issue is resolved when Fry is ressurected, and Robot Fry and Leela decide to hook up with each other.
On The Secret Saturdays, the Saturday family and their nemesis, V.V. Argost, go through the entire first two seasons, to retrieve clues that would help locate Kur, only to find the surprising truth. The Antarctic Cryptid that they fought wasn't Kur, but that cryptid-controlling Zak is (and has always been) Kur...
Spongebob Squarepants: In "Hall Monitor," Spongebob and Patrick are out to catch a maniac, who broke through open windows and caused car crashes. Turns out Spongebob's the maniac. He found that out after rampaging blindly through the city while stuck in a mailbox.
In LEGONinjago, Zane has gone his whole life not knowing if he actually has any parents. Guided by a mysterious falcon, he eventually stumbles upon a hidden laboratory. He first discovers the falcon is actually a robot, then sees mysterious blueprints. Moments later, he realizes these aren't just any blueprints... they'rehis.
In Young Justice, Red Arrow was the most adament about finding the mole in the team. It would turn out that he was unknowingly the mole and while under mind control, he put the entire Justice League under mind control as well. In the next episode it goes From Bad to Worse. He isn't even the real Roy Harper, but a clone created to be the villains' pawn.
One incredibly sad example is that of David Reimer. He and his twin brother were being circumcised shortly after birth, but the careless doctor burnt off his entire penis. Therefore, he was sexually reassigned as a girl. He appeared to be feminine in the first few years of life, but then exhibited wholly masculine traits, leading to a mental breakdown in adolescence when as a social female he underwent aspects of male puberty despite having had estrogen treatment. At this point he finally learned the truth from his parents. He transitioned to male much as an FTM transgender person does, but felt haunted the rest of his life by the lies of his childhood, eventually culminating in his suicide (as well as that of his twin brother) at age 38. It didn't help that at this point he was already a textbook example in university sociology classes about the limits of social conditioning.
There's a museum in Galveston, Texas that had an exhibit on the world's most dangerous creatures, with pictures and a few of the smaller ones. At the end of the exhibit, there's a picture of "The deadliest creature in the world". There's only a mirror.
According to a "Ripley's Believe It Or Not" cartoon, a man was put in prison for attempted murder. It took years to find out who the man's would-be victim was, and it was eventually discovered it was himself!
A white supremacist who wanted to create a town just for white supremacists and Neo-Nazis was shocked late in 2013 when a DNA test revealed he was 14% Sub-Saharan African. To be expected if you know about genetics and biology, but it was contrary to the ardent white supremacist's expectations.
While studying brain scans to search for patterns that correlated with psychopathic behavior, a certain neuroscientist found that his own brain fit the profile.
This last was replicated by Eli Roth in a documentary that the director filmed and hosted for the Science Channel about sociopaths and psychopaths. In addition to detailing many other tests that determine sociopathic and psychopathic tendencies, the director underwent a complete psychological profile, and thus found out that he possessed many of the traits that are commonly thought of as "sociopathic."
Inverted example, where the revelation in question was a surprise to everyone except the person it was about: the Mistaken Identity case of Laura van Ryn, a college student who was in a major accident with several other classmates, including another blonde student who closely resembled her, Whitney Cerak—thanks to the injuries sustained, her being unable to speak for a number of months after the accident, and the placement of a purse at the crash site, Laura's family sat by her bedside and did all they could to take care of her while Whitney's buried and grieved for the daughter they'd lost...only for everyone to discover the girl in the hospital was actually Whitney. It was made worse by the fact that the hospital staff was so convinced of their identification that they in turn dismissed Laura's family's suspicions and encouraged them to believe their daughter's written notes about her parents' names and calling them "false parents" was a case of amnesia or brain damage...so that until the truth came out, Whitney was in the position of actually knowing the truth, but unable to convince anyone of it. It would be easy to imagine her eventually losing her mind, unable to determine what was real or coming to believe she actually was Laura, if the mix-up had been sustained any longer.