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Alternate Identity Amnesia

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This trope is about characters with a form of Involuntary Shapeshifting or Superpowered Evil Side that causes them to suffer amnesia whenever they transform to their alternate form or self. Typically this trope is most often used in media with werewolves (or any other sort of werecreatures), though characters with a Jekyll And Hyde style Split Personality, Demonic Possession, Mind Control, or an Enemy Within may also suffer from this form of amnesia. When it happens it may be immediately noticeable to the character; they will freak out at suffering blackouts and waking up naked in a field, covered in blood, and surrounded by animal carcasses.note 

In some cases the amnesiac lycanthrope actually suffers a combination of Laser-Guided Amnesia and Weirdness Censor about the Missing Time; they might spend weeks, months or years unaware of their condition. It helps if they transition into a type of "sleepwalker" that walks home and cleans up post transformation. The smarter the alternate form is the likelier this is to happen, since it'll likely want its host to stay unawares as long as possible.

One dangerous possibility is for characters to become a Zombie Infectee who willfully ignores or rationalizes away any evidence, symptoms, and lost memories. Whether they cop to it or not, expect Amnesiac Dissonance to kick in once they feel the weight of their crimes.

Typically the memories are merely repressed and come back in a Past Experience Nightmare flashback sequence. If the lycanthopy can be controlled, then learning to do so usually enables the character to remember past events as well as remain lucid and in control during future ones. Occasionally the memories really are irrecoverable, usually if the character is essentially comatose while someone/thing else is in control.

The explanation for the blackouts is usually that "the wolf" has taken over and puts the character to sleep or in the passenger's seat. It's worth noting that the alternate identity isn't necessarily hostile to the character note  and in these cases both personalities may try desperately to find means to communicate.

This is sometimes used as a handy way to keep up The Masquerade from outsiders. If any Innocent Bystanders happen to be transformed, brainwashed, or possessed, they’ll likely have no memory of what happened upon being restored to normal.

Contrast And I Must Scream, when the lycanthrope is aware of what's going on but helpless to stop their wolf-self. Compare What Did I Do Last Night?, the alcohol-induced version. Compare The Killer in Me, especially the "Amnesiac Killer" type. Compare Trauma-Induced Amnesia, which is also fairly common in disassociative disorders. Compare also Identity Amnesia and Amnesiac Dissonance.

This is probably the most "realistic" presentation of classic multiple personality/dissociative identity disorder — the individual identities may not be aware of the existence or experiences of the other identities, and consequently suffer from time disturbances. It's one of the most frightening things about Real Life multiplicity, especially considering its use in this trope, to the point of stereotype. People in real life who know they're multiple may not come out even to close friends, fearing it's the first thing that'll come to mind. Amnesia is also not true for all real-life multiples across the board, and if someone tells you they do know what their other selves said and did, they are likely telling you the truth. Today's psychotherapy for multiples focuses not on fusion but on communication. Many have worked out their own system, leaving notes or voicemails for one another.


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    Anime & Manga 
  • Ayakashi Triangle: Matsuri spends some time hypnotized into believing he was always a girl, showing a completely different personality that lacked any of his original memories. After changing back, he regards the things he did (including falling in love with Soga) as a "weird dream" that he doesn't dwell on.
  • In the 38th episode of the Bakugan anime’s first season, one of the main villains, Masquerade, finally reveals his true identity to the Battle Brawlers after Dan defeats him... and as it turns out, he was Alice Gehabich, the Battle Brawlers‘s team strategist all along. Long story short, Masquerade is actually a Split Personality that was created when Alice caught got up in a freak lab accident involving her grandfather, a dimensional transporter and the negative energy of the silent core. Whenever Alice switches places with Masquerade, she doesn’t remember what he does while he’s in control of their body. And to make things worse, he’s been using her to spy on the Battle Brawlers all along since the beginning of the show without her knowledge or consent. After Dan defeats Masquerade, Masquerade finally sets Alice free and allows her to remember what she did as Masquerade. Naturally, she is horrified and heavily blames herself for all of it.
  • In Bleach, Ichigo's involuntary Hollowfications cause him to black out. After he returns to normal after battling Ulquiorra in his Hollow form, he doesn't remember anything that happened during his rampage. When he finds out that he was responsible for destroying his opponent's arm and leg during the fight, he demands that his be cut off too, otherwise the fight wouldn't be fair.
  • In Demon Slayer: Kimetsu no Yaiba, this is initially an intrinsic part of Zenitsu Agatsuma, one of the series' main characters. He has abysmal self-esteem which, coupled with his cowardly nature, makes the boy firmly believe he amounts to nothing as a warrior despite being a certified Demon Slayer who has survived everything thrown at him. All of this pushed Zenitsu to create a kind of trance mode while falling asleep to answer the need of fighting demons because few people believe in him, which clashes with his own fear pleading him to run away. As such, the trance mode temporarily turns Zenitsu into a fearless man; but when he wakes up he doesn't remember anything that happened during it, with his innate self-doubt reinforcing that he is not a warrior.
  • In Dragon Ball:
    • Saiyans are capable of turning into Great Apes by looking at the full moon. While it is possible to learn how to control this form, Saiyans who don't control it become powerful mindless creatures that go on a rampage and don't remember what happened while in their Great Ape form. This is why Goku was unaware that he killed his adoptive grandfather as a Great Ape.
    • Launch/Lunch was a girl with a Split Personality, whose two personalities, while aware of the other's existence, were unable to remember what the other does upon taking control of the body.
    • In the Dragon Ball Super anime, Universe 6 Saiyan Kale originally didn't remembered what she did once she entered her Berserker form. However, this stops once she learns to control that form.
  • Played with in the Garden of sinners: at the beginning of chapter two, Shiki and SHIKI share their body peacefully, and when one controls it, the other can remember everything they did afterwards. However, as a rift begins to form between the two personalities as a result of the plot events, SHIKI starts hiding his actions from Shiki, leaving her unable to remember what he did while in control of their body.
  • Wolf Man Shishido Shirou/Shiho from My Monster Secret transforms from male to female whenever they look at the moon (or a picture of the moon). Shirou's typically asleep whenever female Shiho is in control of their body, while Shiho herself doesn't have this problem.
  • In the occasions when Naruto entered the Version 2 stage of the Kyuubi's chakra cloak, he completely forgot what happened during those rampages, such as almost disembowelling Jiraiya and trying to kill Sakura.
  • Harumi Chono in Paranoia Agent has DID, and doesn't remember what she does at night as Maria the prostitute. The only evidence of what's going on with her alter is the messages on her answering machine. It's implied at one point that Maria is actually the original identity, with Harumi being an alter that took control.
  • Sailor Moon: This happens with Mamoru Chiba and his Tuxedo Mask persona at first, but after some crystals restore his memories, he is able to remember and Tuxedo Mask just becomes a transformation for him.
  • This is justified in W-Change!!. Maki is unable to remember anything she did as "Dark" Maki, because she hates / rejects her more violent side and tries to suppress her, so the "Dark" personality hides her actions from the "Light" side. After she embraces the "Dark" personality as a part of herself, she can remember her other self's actions just fine.
  • In Yu-Gi-Oh!, Ryou Bakura doesn't remember anything from the episodes when he is taken over by the spirit of his Millennium Ring, seemingly unless the spirit intentionally allows him to. Conversely, the spirit seems perfectly aware of whatever Bakura experiences. Early episodes suggest this was also the initial relationship between Yugi and the spirit of the Puzzle before they forged a partnership. This is, in fact, how it was portrayed in the manga.

    Asian Animation 
  • BoBoiBoy: The titular character when transforming into his fire elemental in the night unknowingly. He unwittingly unlocked this power as a result of accumulating stress as a hero, then would sneak off in the night as BoBoiBoy Fire, with no memories of his pyrokinetic actions when he returned to normal, save for his nightmares of the arsonist, who he didn't know was him. Cue his My God, What Have I Done? reaction upon realising he was the cause of the arson incidents around the island.
    BoBoiBoy: These are merely my dreams!
    Adu Du: Dreams?! Or are they your memories huh?!
  • In the Mole's World animated series, Molele can transform into a superhero called Mole Man. However, Molele doesn't know he can turn into Mole Man, nor does Mole Man know he's actually Molele.

    Comic Books 
  • Both incarnations of Rose and Thorn of The DCU:
  • The Incredible Hulk: Zigzagged as there have been periods when Bruce Banner cannot remember anything about what happened when he was the Hulk (and vice versa) times when the memories are kind of fuzzy, and other times when one or both of them remember the other's actions clearly.
    • Invoked in an issue of Secret Avengers: Banner is dropped onto a squadron of rampaging Iron Patriot drones, and when he reverts to Banner, he's arrested by S.H.I.E.L.D. as part of a plot to recapture the Patriots. He doesn't remember being recruited or fighting. This is partly due to the usual amnesia and partially because S.H.I.E.L.D. has memory-altering technology.
    • She-Hulk experienced this twice: First, during the "The Cosmic Squish Principle" arc, when her savage Grey form first manifested. And later, during the Avengers arc "The Search for She-Hulk", as the exposure to fellow Avenger Jack of Hearts (who can manipulate radiation, although he isn't always able to do this consciously) caused Jennifer to lose control of her She-Hulk form. In both cases, she returned to normal a while after.
    • This happened to Amadeus Cho in Totally Awesome Hulk whenever his Dark Hulk persona took control of their Hulk form.
  • Robin (1993): Stanley Baumgarten thinks he just has a sleep disorder when instead the mystical entity the Dark Rider has been possessing him at night and making money as a magic using assassin in Stan's body. He is horribly confused the first time he wakes up on the sidewalk in cuffs.
  • Spider-Man:
    • Norman Osborn is sometimes unaware of the Green Goblin's actions (most notably, the Goblin knew Spidey's secret identity, but Norman didn't).
    • This was also the case with Martin Li/Mr. Negative for a long time, with Li apparently unaware that Negative even existed (by contrast, Negative knew of Li but left his life alone).
  • Ms. Marvel: When Carol Danvers started out as a superhero, she would involuntarily black out and change to her alter ego. She wasn't initially aware that she was a superhero. After a while, the line between the two started to blur, and they began fighting over who was in control, until the issue was resolved.
  • Blaze of Glory: Lance Temple remembers nothing from his actions as the Outlaw Kid, other than a vague feeling that he had been there.
  • Wonder Woman Vol 1: This is how Cheetah (Priscilla Rich) expressed her multiple identities in the Silver Age, with the Cheetah and Priscilla being unaware of each others' actions unless they saw physical or documentary evidence of it, and consequently try to foil their other persona's plots. In the Golden Age she was a vain murderous socialite who took up a costumed alter ego when superheroes were getting more attention than her.

    Fan Works 
  • In The Beast Of Gusu, when under the effects of the Wen drug, shifters have no recollection of what they do in their animal forms. Therefore, the first time he’s drugged, Wei Wuxian doesn’t even realise he’s been shifting the whole night. The second time, he runs away and wanders for three months, not remembering that he’s a shifter and has a human form.
  • Specter in Infinity Train: Knight of the Orange Lily doesn't remember anything when his Split Personality Easternote  takes control except a splitting headache caused by Paul London knocking Easter out with his staff. Even when Gladion, London and Tokio spell it out for him, he's in disbelief. By the time they reach the Windfish Car, he becomes horrified whenever he switches back.
  • In Nullius In Verba, not only are the Akuma transformations permanent, but they no longer can remember who they were before or that were people before Hawkmoth transformed them. They are forced to follow Hawkmoth's commands, sent out only to attack the heroes. The story focuses on Lady WiFi discovering she was once a girl named Alya Cesarie and finding a way to break herself and the others free from Hawkmoth's controls.
  • In Secret Keepers: The kwamis deliberately suppress their chosen's memories to make them more efficient in fighting the akumas. As a result, Ladybug and Chat Noir can't remember who they are as civilians when active, while their civilian selves have no idea about the kwamis or their time as heroes.

    Films — Live-Action 
  • David from An American Werewolf in London doesn't remember anything about the night he transforms and attacks a young couple, some hobos, and a Tube commuter.
  • Werewolves in Are We Monsters have their minds go into a dreamlike state (as Maya narrates, said dreams are more like nightmares) as their bodies mutate into grotesque un-lupine monsrosities that can only hunt and devour.
  • Bloodthirsty: Grey had blacked out when she fully transformed and killed Charlie. The very ending's shots of her eating Vaughn's flesh in wolf form imply she was able to control her form now that she realizes what she is.
  • In Carry On Screaming!, this happens to Sergeant Bung after he is fed the Mr. Hyde serum.
  • The protagonist in Fight Club doesn't remember any of his alter-ego's activities.
  • Joel of Good Manners has little to no recollection of his actions as a wolf and somehow doesn't connect the dots on the exact reason he has to be locked in a cell every full moon night (suggesting he doesn't even know he is a werewolf, or if he does, he doesn't think he's dangerous). He only realizes the reasons when he is at the dance with Amanda, just a little too late.
  • The two leads in Ladyhawke are cursed to be a hawk and a wolf at different times of day and evidently don't know what happens when they aren't human. They actually seem to be replaced by the animal they become, with that animal's instincts and desires — which is particularly dangerous when Etienne of Navarre is in wolf mode.
  • Marvel Cinematic Universe: Zigzagged, as sometimes Bruce Banner cannot remember anything that happened while he was the Hulk (i.e. the years spent on Sakaar between Avengers: Age of Ultron and Thor: Ragnarok), and sometimes the memories are fuzzy or even clear (i.e. in Avengers: Infinity War he explains to other Avengers what happened to Thor and the Asgardians while he was "hulked out").
  • In Me, Myself & Irene, Charlie Bailygates can't remember his behavior or words when his bad mood shifts into Hank.
  • In Werewolf: The Beast Among Us the werewolf's human persona is completely unaware of their full moon activities and has been since birth.
  • Wolf Blood, one of the first werewolf movies ever made (it was filmed in the 20's and is silent) has the lead character suffer from this amnesia so completely he doesn't remember if he went out and killed the rival logging boss who almost killed him earlier. While the film itself never actually definitively says he did it or if it was a normal wolf attack, his inability to remember any of the last evening send him across the Despair Event Horizon. He even starts running after the wolf spirits he is now able to see— off a cliff! Thankfully, his love interest stops him in time.

  • The titular Captain Underpants doesn't share memories with Mr. Krupp, being a product of George and Harold's hypnosis.
  • The Dark Tower: In The Drawing of the Three, Odetta Holmes and Detta Walker are not just unable to access each others memories, they actually make up false memories to fill the blancs left by when the other is in control. This is why they are completely unaware of each other, untill the end of the story.
  • Harry Potter:
    • Harry Potter and the Chamber of Secrets: Ginny Weasley finds she's having days where she wakes up in one room and has no idea how she got there, over and over. Gradually she starts to put it together that the diary of Tom Riddle is possessing her in order to unleash the Basilisk.
    • Ginny's experience gets a Call-Back in Harry Potter and the Order of the Phoenix. Midway through the book Harry fears that his dreams telling him what Voldemort is doing are because the Dark Lord is possessing him. Ginny quells him of this fear, pointing out that he hasn't had any periods of amnesia just like she had when being possessed.
  • In the New Jedi Order, Tahiri experiences this after being freed from being nearly Brainwashed and Crazy; though she remembers ideas and concepts that were implanted, her specific memories of what Riina did quickly fade. Later, when Riina resurfaces later in the series, Tahiri blacks out whenever she assumes control. It turns out that this doesn't work both ways; Riina remembers everything Tahiri does, but is ordinarily powerless to act unless she manages to wrench control of their body for a short time. After pulling a Split-Personality Merge, however, the "new" Tahiri has access to the full memories of both personalities.
  • In Newshound, Heather's recollection of her time as a wolf is fuzzy at best, leaving her to piece together what she did the night before based on physical evidence and whatever flashes of memory she can extract from her lupine half.
  • Seekers: At first, Ujurak forgets he's a bear when he's in another form. He finally figures out how to keep his memory in Fire in the Sky.
  • The Supernaturals Series: Main character Daniel Price is a werewolf who at the best of times only has vague recollections of what he does while in wolf form.
  • Occurs to True Conductors in the web fiction Six Chances due to a Psychic Link. One True Conductor can override and take over another one that they are connected with, and the person who gets overriden usually doesn't remember what occurred during the override. This also happens to Francis who takes on the memories of Theta.
  • Despite its prevalence in modern adaptions, this trope is averted in the original version of The Strange Case of Dr. Jekyll and Mr. Hyde. Both personalities are aware of the other's actions, as Hyde is simply the personification of Jekyll's dark side.
  • In The Reformed Vampire Support Group, werewolves have this. It comes up more in the sequel: the protagonist, Toby, was taken to the hospital after being found naked and unconscious in a dingo pen. While he and his mother look into various medical explanations for his blackout, Reuben and Father Ramon try to convince him that he actually had his first transformation.
  • Hazel in The Darkest Part of the Forest has no idea that at night she becomes a knight in service to the Alderking.

    Live-Action TV 
  • Buffy the Vampire Slayer:
    • At the end of "The Pack" where several students are possessed by hyenas, Xander says he doesn't remember what happened during that time. Giles privately confronts him, saying none of his books about such possession reference amnesia as a symptom, and Xander admits he just doesn't want to talk (or think) about his actions, which include eating a live pig and nearly assaulting Buffy
    • Buffyverse werewolves start out with a classic case of this trope, not remembering anything of what they did during the full moon, but as the time they have been cursed lengthens they will start to remember bits and pieces.
    • During Season 5, the current Big Bad, Glory, is eventually revealed to be a god who was cast out of her home dimension and trapped in a mortal body, Ben Wilkinson. While Glory has grown strong enough to take control of her host, for most of the season she and Ben were simply aware of each other's existences without sharing memories, to the extent that Ben knew that Dawn Summers was the Key that Glory was searching for while Glory didn't.
  • Heroes: Nikki is like this when her alter-ego Jessica first starts taking over her body.
  • A variant on House of Anubis. After regaining their souls, the Sinners had no idea what had happened since being turned, only remembering the moments before getting their souls stolen, or even less. They weren't even aware they had turned evil at all, and were shocked to find themselves in the middle of the trashed school they had spent the day tearing apart. However, the Sinners themselves remembered everything from their "original" self.
  • ''The Imperfects: Juan doesn't remember anything he does in chupacabra form and, almost any time he's told what he's done, he is horrified at his own actions.
  • In Jekyll, a loose modern adaptation of The Strange Case of Dr. Jekyll and Mr. Hyde, Tom Jackman has no memory of anything that happens when the Hyde personality takes control. Somehow, they've reached an agreement whereby, if something happens to one which they think will affect the other, they leave a message on a Dictaphone that the other personality can listen to when they regain control.
  • Knots Landing: In Season Six, Valene has a nervous breakdown because no one will believe her when she says that she heard her supposedly stillborn babies cry after they were born. She loses her memory and comes to believe that her name is Verna Ellers, taking a job as a waitress in Shula, Tennessee. Notably, Val's alternate identity contains traces of her real one as her initials are V.E., she is originally from Tennessee and she worked as a waitress before she moved to Knots Landing.
  • Misfits parodies this with one character. The power he got from the freak lightning storm was to "turn" into a terrier... In mind only. He goes around naked and acts the super friendly puppy, with no memory of it the next day.
  • In Mr. Robot, Elliot, who suffers from dissociative identity disorder, has large gaps in his memory from when Mr Robot takes control over him. A notable example of this is when Elliot - under the control of Mr Robot - threatens Romero with a gun, something Elliot has absolutely no recollection of.
  • In My Own Worst Enemy the main character has as close to a benevolent version of this trope apply. He's a spy with a manufactured cover identity which can be turned on and off by a chip. When the chip starts malfunctioning, both personalities have to communicate via short video messages to avoid compromising the spy's cover.
  • Red Riding Hood in Once Upon a Time suffers from this regarding her werewolf transformations and murders. However, she eventually learns to control her wolf self.
  • In Power Rangers: Dino Thunder, initially Trent doesn't remember what he does when the White Ranger dino gem takes control. Eventually, he remembers, but can do little to stop it. This proves to be a bad thing - after a certain point, his dark side is in control all the time. Eventually, the gem is drained of some of its energy, resulting in Trent being himself full-time, but at the cost of some of its power. For once, the way a Sixth Ranger is never quite as powerful after his early appearances is justified.
  • Werewolves in Supernatural suffer memory blackouts when they transform.
  • The premise of Severance (2022) is that people are given chips in their brain that makes them lose their memories of the rest of their life when they are working at Lumon corporation and likewise have no memory of what they did at work when they are outside of it, giving them two separate identities that have no recollection of each other.
  • Teen Wolf
    • Werewolves who were recently bitten are unable to control their changes or remember their actions in wolf form. This stops once the werewolf learns to control their wolf form.
    • The Kanima in season two has no memories of what they do when transformed.
    • In season 3, Stiles is possessed and appears to have no knowledge of what he does when the thing possessing him takes control.

  • Binary Break: After being purified, Nekomon not only doesn't remember attacking the kids when he was corrupted, but staunchly denies having done so and says it must've been somebody else.
    Nekomon: I think these woods are pretty dangerous so I'm gonna, I don't know, try and find somewhere safe to be. I heard there were these weird monsters in here.
    Penny: Yeah you were one of 'em!
    Nekomon: Mm, I don't know about that.

  • In Dawn of a New Age: Oldport Blues, Simon doesn't remember what happens when his evil Dark Dragon personality takes over. He was rather shocked when he regained control at one point and found himself stark naked and stuck in a tree. In another instance, he came to consciousness, found himself wearing the all-black ensemble that Dark Dragon put on, and came to the conclusion that someone had dressed him up in his sleep.

    Tabletop Games 
  • Call of Cthulhu, Masks of Nyarlathotep campaign. In "The Derbyshire Monster" adventure, a young woman named Eloise Vane is under a curse to become a werewolf on nights with a full moon. Every time she becomes a werewolf she doesn't remember what happens but has evil dreams of ghastly happenings (her attacks on other creatures).
  • Dungeons & Dragons:
    • The 1st Edition Dungeon Master's Guide said that when a person changed into a lycanthrope (by being bitten by one) first started changing to wereform on nights of the full moon, the next morning they would not remember what happened the night before.
    • Ravenloft supplement RR7 Van Richten's Guide to Werebeasts. In Ravenloft, when an infected lycanthrope involuntarily changes to wereform it will not remember what happens while it's transformed.
      • From the same setting, Tristen Hiregaard doesn't remember what happens when he transforms into his evil alter-ego Malken, but Malken is fully aware of what Tristen does.

  • The Transformers G1 toy Punch has this issue. Normally an Autobot, he has an alternate robot mode who's a Decepticon, Counter-Punch. Initially, Counter-Punch was just a cover that Punch used to spy on the Decepticons, but then he started having blackouts and waking up in strange locations.
  • Monster High: Usually, Jackson Jekyll and and Holt Hyde can't remember consciously what one of them does upon taking control of the body, to the point of not knowing about the other's existence or that they were the same person. However, Jackson's journals suggest that they can subconciously retain the other's memories, as Holt managed to recognize Draculaura in spite of never having met her before.

    Video Games 
  • Cynthia Wit in Arcanum: Of Steamworks & Magick Obscura has no idea that she's a lycanthrope, or that she's responsible for butchering the rabbits that her father farms. She tells you that she's been hoping to catch the culprit herself, but all she remembers is feeling terribly exhausted, falling asleep before the attacker arrives and waking up the next morning to find another dead rabbit.
  • In The Elder Scrolls series, the standard way of becoming a were-creature involves the disease which causes it being transmitted via a wound inflicted by the infected individual. There is typically a 3-day "incubation" period during which the disease is mild and easily cured. However, the disease can be transmitted directly and instantly by consuming the blood of an infected Lycanthrope. Conversion using this method causes an instant "unusually intense" transformation, often accompanied by amnesia. Later transformations do not have this amnesia. This latter method is how the Dragonborn becomes a werewolf in Skyrim. There, the player retains control of the character in werewolf form for a short time before the screen fades to black. Afterward, the Dragonborn is suddenly in a forest far from their original position, is naked, and their dialogue suggests they have no memory of what occurred. This only apply to the first transformation though; after this, you have complete control over your lycanthropy and suffer no amnesia.
  • In Elsword, Ara's backstory has this. After she gained the mystical hairpin with a Kitsune spirit sealed within and almost get killed by her brainwashed brother, she gets unconscious. The next thing she knew after she "woke up" is that she had battled her brother and the demon army unconsciously - it's the fox spirit that did it for her.
  • One blink-and-you'll-miss-it line in Boktai 2: Solar Boy Django states this is a drawback to using his Superpowered Evil Side along with losing control of his actions. Not that this affects the game in any way.
  • In The Sims 3 Werewolf Sims that transform back into humans will get a moodlet saying they don't remember what just happened, but they have the feeling it was "something awesome".
  • In the Galaxy Angel II trilogy, Kahlua Marjoram loses all awareness when she transforms into her Sexier Alter Ego, Tequila. On the other hand, Tequila retains all the memories from Kahlua as well as her own.
  • In Fire Emblem Engage, Veyle is revealed to have an evil side which carries Sombron's bidding with glee, whether it be killing the loved ones of the main characters or putting innocents at risk just to try and kill them. Her normal sweet self is completely unaware any of this is happening, so to say she's horrified upon learning of her other self's atrocities is an understatement.

    Visual Novels 
  • Amnesia: Later has Ukyo and his split personality, the other Ukyo. One isn't aware what the other is doing while the other is in control, so they find themselves in places they don't remember going to and having done things they don't remember upon switching. This has led to them choosing to write notes to each other to work around this problem, even if it's mostly used to complain about household chores not being done.
  • In Danganronpa, Toko Fukawa and her alternate identity Genocide Jack both have this. The former is a meek self-deprecating girl, the latter is a notorious Large Ham Serial Killer. Neither of them share memories with the other one, being left to just deduce what happens when their other side is in control.
    • Exploited in Danganronpa: Trigger Happy Havoc. When their shared body is hit with a dose of Laser-Guided Amnesia, only Toko was affected. This means that Jack remembers The Tragedy — unfortunately, she's unable to provide any concrete details, as it was Toko who actually experienced it. It’s also played for laughs, as the only reason Jack never said anything, despite everyone wanting to know how they ended up in the situation, is that nobody asked her.
    • Ultra Despair Girls expands on this a bit. While Toko and Jack still don't share memories, it's said that the two of them share knowledge and emotions. So if one feels affection for someone, the other will feel the same way. This is why Jack eventually warms up to Komaru Naegi over the course of the game, as despite being a serial killer, Toko's own growing affection for Komaru prevent Jack from hurting her.
  • Extra Case: My Girlfriend's Secrets: Sally has episodes where she doesn't remember what she was doing. She is almost never conscious at the same time her Split Personality, "Seira"/Shadow, takes over her body, though she does sometimes have vague dreams about the latter's crimes.
  • In My Magical Divorce Bureau, Baird the werewolf has this between his human and wolf forms. This is why with his marriage to Lexis is a problem — his human self agreed to it but his wolf self did not, and Lexis didn't know the latter fact.
  • Owen, the hidden fourth personality within Uendo Toneido in Phoenix Wright: Ace Attorney – Spirit of Justice. He witnessed the murder of Taifu Toneido, something none of the other personalities know about, so the main personality actually took steps to rearrange the crime scene, removing evidence which implicated Owen.

    Web Animation 
  • Flippy of Happy Tree Friends fame isn't able to remember any of Fliqpy's actions and doesn't seem to be even aware of his existence until the "Double Whammy" two-parter.

  • Dean & Nala + Vinny: On one occasion, Nala transforms into her savage alter ego Jungle Cat Nala at the sight of a bird outdoors. Despite Vinny's plea of "Nala, NO!", she kills a bird. When she transforms back into her regular cat self, she freaks out and asks who left a dead bird at her feet.
  • An alternative version in Girl Genius, with Big Bad Lucrezia's possession of Agatha. Neither of them can remember anything that happened while the other was in control of Agatha's body, which leads to more than a few issues when Lucrezia puts plans in place that no-one then knows about - one example being the wasping of Baron Wulfenbach, leaving him susceptible to Lucrezia's commands. No-one knows that he's been compromised and could potentially be used as Lucrezia's puppet, at least at first, and he can't talk about it.
  • Hank doesn't remember the actions of her werewolf form in The Night Belongs to Us.
  • In Cans Of Beans, Carl doesn't remember anything that happens to him when he's a werewolf. Which means that, until the end of chapter two, he has no idea that his werewolf form, "Billy," is a sapient and friendly Split Personality who actually does have Carl's memories.
  • In Dumbing of Age, Amber and Amazi-Girl don't initially have this, but after a later traume, Amber suspects that Amazi-Girl is going on patrol without her knowing. Amazi-Girl subsequently gives up superheroing altogether in favour of roller derby, and it's not clear if Amber knows this.
  • The Secret Knots: In "11 signs you are not getting enough sleep", the werewolf protagonist doesn't remember any of things they did or the people they killed (and ate) while transformed.

    Web Original 
  • This happens a lot in The Slender Man Mythos. In Marble Hornets, the original Slender Man series, Tim aka Masky remembers precisely jack shit about his masked moments. He's not happy to find out about them when he googles the series by accident, hoping to find out how the titular film went.

    Western Animation 
  • Adventure Time:
    • The episode "Hug Wolf" has Finn becoming the titular Hug Wolf, and never remembering anything when he's back in his human form.
    • Simon/Ice King has two main personas: his "real" self, who is a Badass Bookworm and a massive Woobie, and his Crown-possessed self, who is a rather unstable Ineffectual Sympathetic Villain. As the latter, he has no memories of being the former, only subconscious desires. As the former, he has some vague impressions of what he did while under the Crown's influence but no concrete memories.
  • American Dad!:
    • Roger has an ongoing rivalry (based totally on Disproportionate Retribution, because this is Roger we're talking about) with an unseen adversary... until we learn that the unseen adversary is in fact one of his (many, many) personas! Slight subversion, in that far from being evil, the persona is actually a decent human being--um, person, that took on a life of its own because of the trauma of Roger caring for someone else. Eventually, Roger kills the poor guy because he'd just "slow Roger down".
    • Stan ends up going through something similar in "Cock of the Sleepwalk"; after his 100th kill, Stan keeps waking up to discover he's been doing good deeds he can't remember in his sleep. Eventually, Stan watches a video made by "Sleepwalking Stan" explaining everything: "Sleepwalking Stan" is Stan's long-suppressed conscience, determined to atone for all the people Stan's killed and to ensure that Stan never kills again.
  • Though it never happened onscreen in Ben 10, Word of God stated that it happened to Ben with Ghostfreak, which was when he called his minion to pull out the Thanatos Gambit that serves as the main plot of season 3.
    • Played straight with Big Chill in Ben 10: Alien Force, where Necrofriggians' reproductive instincts cause Ben to regularly turn into Big Chill unconsciously and go around eating metal. Ben keeps no memory of those transformations.
  • The episode of Cybersix where Lucas is infected and turns into a werewolf have him suffer from these memory blackouts. Notably, he's able to use The Power of Love and Heroic Willpower to break through the animalistic domination of his werewolf mother and help Cybersix.
  • The title character of Fangface has no memory of his human self, and even when he transforms back into his regular form again, he also has no memory of his werewolf self as well.
  • In the Futurama episode "The Honking", Bender becomes a were-car and has no memory of doing anything whenever he leaves this form.
  • In a Legion of Super Heroes (2006) season 2 episode, Timber Wolf fears he's losing control of his transformation into his more feral state, the symptoms were mainly headaches and memory loss. However during one of his blackouts he ended up murdering his father (actually a clone of him) in a fit of rage and in the aftermath, he was hounded by most of the Legion for the crime. The memory loss and headaches were caused by nanites his real father used to control him in an elaborate scheme to get him back.
  • Miraculous Ladybug: The Akumatized villains that Ladybug and Chat Noir fight have little or no memories of being villains once they've been returned to normal (Word of God describes it as feeling like a dream they can't remember). However, as demonstrated by Nathalie, Lila, and Chloe later in the series, this is not the case if they were willingly helping Hawk Moth.
    • This also happens most of the time when the villains have the ability to brainwash people themselves, which is often done to Chat Noir, who doesn't remember things like the Puppeteer taking control of him, or Malediktator making him act like an actual cat.
  • Mr. Bogus apparently suffered from this in the first act of the episode "Nightmare On Bogus Street". After Bogus becomes a werewolf from drinking a potion that he created, he puts Brattus in a stewpot, when he suddenly turns back into his regular form once again, confused about how Brattus got into a stewpot. When Brattus explains to him what happened, Bogus denies ever doing such a thing to his own cousin, until he turns back into a werewolf again.
  • OK K.O.! Let's Be Heroes: In the episode "Let's Get Shadowy", it's revealed that Professor Venomous and Shadowy Figure are the same person, as Shadowy Figure is Venomous's Turbo alter-ego...with the extra twist that Venomous himself was unaware of this, and truly didn't realize that this was the cause of his constant exhaustion and irritability. He's genuinely horrified when he finds this out, entering a Villainous BSoD because of it.
  • The Owl House: Eda the Owl Lady is unable to remember anything she does when she changes into her cursed form.
  • Sofia the First:
    • In "Two Princesses and a Baby", when James is turned back to normal, he doesn't remember what he did as a baby.
    • In "Mystic Meadows", when everyone at the Conjuring Contest is turned back to normal from being snowmen, they don't remember what happened when they were accidentally transformed into them by Goodwyn and Cedric earlier. Thus, Sofia and Cedric's team isn't disqualified for initially doing the spell wrong, allowing Cedric to conjure up the winning answer for it: a snowman.
  • Steven Universe: Gems who have been under White Diamond's control have no memory of it after, as hinted by Pink Diamond's original Pearl when she asks what happened after being freed, and confirmed in Future when she says she doesn't remember anything from the 8,000 years she was in that state.

    Real Life 
  • A more long-term example: David Bowie retained little memory of recording the album Station to Station, during which he became Lost in Character as the Thin White Duke. As Rick James once said, "Cocaine is a hell of a drug."
  • There were many online discussion groups for multiples in the 1990s and 2000s. One list manager dubbed this trope "Gloria in a Ballgown" from the stereotypical Sybil-type image of waking up in an unfamiliar town wearing unfamiliar attire and people are addressing you with an unfamiliar name.