Amnesia Loop

Marlize: How many times have I been through this?
Clifford: Too many.

— The Flash (2014), “Null and Annoyed”

A character notices something unusual, investigates it, discovers a big secret, and is given Laser-Guided Amnesia to keep the secret safe. All is well... until they notice the unusual thing again, and since they have no memory of last time, start the exact same investigation all over again.

Stories involving an Amnesia Loop are often told from the point of view of the investigating person, with "this isn't the first time this has happened" coming in as the big twist. Doing it that way also lets the writers establish the repetition without making the audience sit through it more than once.

May end with a Here We Go Again!. Contrast "Groundhog Day" Loop where the character is fully aware of the repetition. See Amnesiac Resonance when information from a previous loop seeps into the current one.

A situation where an investigator is pursuing a single investigation while hampered by a faulty memory, as in Ghajini, is not an example of this trope, unless it includes the specific situation where the investigator completes the investigation and then starts over because they've forgotten that they completed it.

Spoiler warning: Because of the "big twist" aspect described above, the fact that a particular work is listed as an example may be a spoiler in itself. Spoilers of that nature will not be hidden in the list below, because there is no point in an example if the whole thing is hidden.

Other spoilers, such as the nature of the secret being protected, may be hidden as usual.

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Examples:

Anime & Manga

• Miumiu in JoJo's Bizarre Adventure: Stone Ocean has the Stand Jail House Lock. The victim of her Stand can only remember three pieces of memory from after activation, and if a new memory is created, the oldest is ejected (for example, she puts a cockroach in Jolyne's sandwich, then splatters three condiments on it, so she forgets there's a cockroach). This leads to a cycle of Jolyne figuring out her identity, starting to do something about it, then forgetting in the middle.
• In The Seven Deadly Sins, King erased Diane's memories of their first friendship so she wouldn't see the horror he did in his job. They meet again some years later, starting a chain of events that leads Diane to remember, but Gowther erases her memories again as part of an experiment.
• In Tsubasa -RESERVoir CHRoNiCLE-, every time C!Sakura figures out her missing memories are about C!Syaoran (the ones she sacrificed to travel dimensions), she forgets again.

Audio Play

• The Big Finish Doctor Who audio "Cycle of Destruction" reveals an interesting variation on this theme mixed in with Raised by Wolves. The ALARC research facility keeps its android prototypes contained by a security system that will wipe the android's minds if they leave the base and an automated recall signal that will eventually draw the androids back to the base if they do get out. Unfortunately, since these androids are programmed to learn from whatever they meet, at least one such android was essentially "adopted" by the Caru, a bear-like species that lives on the planet. As a result, when the Caru-android's recall signal was triggered, once in the base the feral android lashed out and caused serious damage while trying to escape, eventually leaving the base, suffering another mind-wipe and starting the titular cycle of destruction all over again.

Comic Books

• Done in the Astro City story "Her Dark Plastic Roots". Beautie, a Robot Superhero based on a fashion doll, is unsatisfied because she doesn't know her own origins, so she begins to investigate the matter. Beautie eventually discovers she was created by Elaine Girbachs, the daughter of Dr. Gearbox, but he denounces Beautie because he believed engineering and math aren't fields for girls. Ashamed, Elaine tearfully ordered Beautie to leave and forget forever. When Beautie confronts Elaine in the present day, she orders Beautie to leave again... and it turns out that this happens every few years as Beautie's directive weakens until she re-visits Elaine again and again and again.
• The DC Elseworlds story Batman/Demon: A Tragedy mixes this with Tomato in the Mirror, with the revelation that Bruce Wayne has been the host for the demon Etrigan for centuries, with Alfred Pennyworth a false identity assumed by Merlin to watch over Bruce. Each time Etrigan manifests from Bruce, the demon starts out going after criminals, but when Etrigan starts to attack innocent people, Alfred/Merlin will reveal his identity and erase Bruce's memory once again, granting Bruce a couple of decades of peace before Etrigan awakens once more and Alfred has to erase Bruce's memory again.
• Justice Society of America: Professor Malachi Zee is repeatedly getting murdered or attacked by his lab assistant Per Degaton to steal his time machine. Once the JSA fixes whatever temporal change Degaton tried to do, everyone forgets and Degaton is back to cleaning test tubes. As a result of the constant conflict between them, Zee continues to work on his time machine, believing that it has failed to work thus far (not remembering it was simply hijacked and its effects have been erased from history).
• Point Blank: This is what becomes of Grifter's attempt to investigate Lynch's shooting, due in no small part to his drinking problem.

Fanfic

• Ash's Adventure: Girls' Hunter Edition reveals that the Nurse Joy of Viridian City is basically stuck in one of these; every time she learns the scale of Team Rocket's influence in the city, she is taken to their base to be interrogated by a Psychic PokeGirl, and then her memory is wiped of the events that inspired her suspicions so that she doesn't remember anything (Team Rocket allegedly consider this simpler than killing her and drawing attention to her disappearance).
• Burning Passion: The story starts out with an amnesiac demonic Sunset wandering what is essentially Hell. Over the story, she gradually recovers her memories as she tracks down Wallflower Bush (who accidentally turned both of them into demons). Eventually, she finds Wallflower, reassures her of her love, and sets off to look for the portal back out of this realm... at which point Wallflower's uncontrolled demon magic erases all her memories. According to Wallflower, this is about the eighth or ninth time this has happened, and she has yet to get Sunset to sit still long enough to explain about the loop.
• Infinity Train FANFIC has this as The Reveal in Chapter 10: Tulip has been stuck on the train for over a century, but she doesn't remember because she keeps getting her mind wiped by the Conductor and sent back to the end of the train every time she fails to beat him. The Timey-Wimey Ball nature of the train (which merges several alternate timelines together) additionally mess with her age and memories of getting on the train. The current loop has her as a 13-year-old, but others have had her as a preteen, older teen, and an adult.
• Step Right In and Start Again: As a side-effect of messing with temporal magic, Starlight is trapped in a personal loop where she wakes up each morning with her memories wiped, beginning each new instance believing that she just gave up her plans for revenge and is about to be judged by Twilight for her crimes, leading her to suffer increasing panic and confusion as the world changes more and more around her. The other side effect is that she's now becoming The Ageless, meaning that she's still stuck in the loop even after the Natural End of Time.

Film — Live-Action

• This is the driving force behind the plot of Before I Go to Sleep.
• In Eternal Sunshine of the Spotless Mind, where technology exists to erase unhappy memories, people keep getting into the same bad relationships over and over, then having their memories of them removed.
• Implied to have happened several times with Leonard Shelby in Memento. Leonard is implied to have killed several people who he thought killed his wife, then destroyed the evidence of "success" after the killings, then was driven to find a killer all over again. If Teddy is to be believed, Lenny killed the person who broke into his house a long time ago and on top of that, it's actually Leonard himself who accidentally killed her, though she's as much to blame.
• Supernatural example in Triangle. Jess keeps losing memory of the previous loop when she falls asleep on the yacht, and one of the first things she says on waking up is "I don't remember.".

Literature

• In Evan Hunter's novel Buddwing, a man awakens with amnesia and starts to piece things together. In the end he remembers that because he was a perpetual dick his wife committed suicide, and the shock and guilt gives him amnesia again. The book ends at the same place and situation at which it started.
• The short horror story Captain's Log reveals that this is why Aliens Steal Cattle - the aliens have anterograde amnesia and are biologically immortal, so they've spend thousands of years doing the same things over and over again.
• The children who are Amnesiac Gods in John C. Wright's Chronicles of Chaos get this repeatedly, until they escape the school.
• In Vernor Vinge's short story "The Cookie Monster", the characters figure out halfway through their investigation that they're uploads in a computer simulation, and that they get reset and forget everything at the end of their work cycle. They do know that the current cycle is different, as they have an email that gives them hints on where to go, but they have to race to the goal before they're detected or the cycle ends. When they reach the end of the line, they find out that they've repeated the cycle of following the email to the programmers' lair over 1000 times already. The characters even make the Amnesia Loop work to their advantage: by tipping off the programmers at the beginning of their cycle, they have a whole subjective year to get closer to escaping, sabotage the controlling scientist's attempts to keep them from noticing discrepancies, and pass on everything they've learned to the next cycle.
• Haruhi Suzumiya: During the short story "Endless Eight", everyone except Yuki has their memories of the "Groundhog Day" Loop erased at the end of said loop. This is a problem, as they are trying to figure out how to end it.
• In There Is No Antimemetics Division, The Antimemetics Division, as well as numerous other similar agencies, have been locked in one of these for decades, possibly centuries, regarding SCP-3125. Every time they become aware of its existence and fail to contain that knowledge, it attacks and destroys everyone even tangentially connected to this awareness. Once this became understood, deliberate, and carefully managed amnesia of it was their only defense.
• Thursday Next series:
  • In First Among Sequels, Thursday finds out that her daughter, Jenny, isn't real. Landen tells her that he has to reveal this to her a lot, especially on bad days. The scene ends with Thursday asking where Jenny is and Landen makes an excuse that Thursday accepts and she moves on.
  • In The Woman Who Died a Lot, Jenny keeps moving around the family. And other things occur that, in hindsight, show that memories were tampered with. Finally, an intervening force straightens it all out, and at their request, lets them believe that Jenny was a real girl who died.
• Yumi and the Nightmare Painter: The father-machine doesn't have enough power to trap the souls of the fourteen yuki-hijo the way it trapped everyone else, but it does have just enough power to erase a day's worth of their memories. So it uses its captured souls to create fake villages and has each yuki-hijo live out the same day over and over again, erasing their memories each night, for seventeen hundred years.
• Zones of Thought: In A Deepness in the Sky, one of the characters is in a relationship with a man who she thinks is really nice but he's really a sadistic monster. There's a scene where she finally discovers the truth, only to be detained by his guards and dragged off to have her memories selectively erased, with the guards' dialogue making it clear this isn't the first time this has happened.

Live-Action TV

• Arrested Development: GOB spends most of 2007-2012 in a "Roofie Circle".
• Black Mirror: "White Bear" is all about the punishment of a woman who watched (and recorded) her boyfriend burning a kidnapped child to death. Her punishment is to have her mind wiped and then chased around for a day by armed maniacs while hundreds of people stop to record her on their phones. Then when the day is complete they wipe her memory and do the same thing again, and again, and again.
• Buffy the Vampire Slayer season 5: whenever a human learns that Big Bad Glory is hidden/trapped inside the body of Ben they forget very shortly afterwards, as Glory's secret is protected by a side-effect of the spell; as a result the Scooby Gang learns this secret on multiple occasions.
  Spike: [laughs sarcastically] Oh, I get it. That's very crafty. Glory's worked the kind of mojo where anyone who sees her little presto-change-o instantly forgets. And yours truly, being somewhat other than human ... stands immune.
  Willow: [frowning] So ... Ben and Glory ... are-are the same person?
  Xander: [slowly, like a revelation] Glory can turn into Ben, and Ben turns back into Glory.
  Anya: And anyone who sees it instantly forgets.
  Spike: Kewpie doll for the lady. [he puts one finger on his nose and points the other hand at Anya]
  Giles: Excellent. [looks around at them] Now. Do we suspect there may be some kind of connection between Ben and Glory?
  Spike: [sigh]
• Doctor Who:
  • "The Beast Below": There's a secret at the heart of the kingdom, and Liz X is determined to uncover the truth. Part of the truth she uncovers is that she's uncovered the truth many times before, but always agreed to undergo Laser-Guided Amnesia to allow it to remain secret. When the Doctor and Amy get involved in her latest investigation, Amy finds a way to Take a Third Option, and the loop is broken.
  • The Silence (being creatures that you immediately forget the second you're not looking at them) induce this in their victims, with the very fact of their existence being the constantly forgotten revelation in their first episode. The problem of forgetting them cannot easily be solved; even pictures of them get forgotten instantly and spoken information about them fades fairly quickly (though not instantly), but people can leave themselves messages and warnings about them, and thus make themselves aware of their existence even when they can't actually remember them.
  • "Asylum of the Daleks": One of the warning signs that Amy Pond is losing her mind is that the Doctor tells her that he's already explained what's happening to her several times.
  • "The Inforarium": The Doctor gets a guard at the titular Great Big Library of Everything stuck in one because he's left a memory-proof recording, so the guard forgets about it every time he looks away. It's not permanent, though.
  • "The Zygon Inversion": The Doctor reveals that the Osgood Box is a fake, and also that there's a reason it's kept in the Black Archive with its Laser-Guided Amnesia device. Before sonicking the memory wipers to do their thing, he suggests they've all already been through this fifteen times.
  • "Heaven Sent": The Doctor is teleported into a mysterious and sinister Mobile Maze. As he explores, he finds evidence that he's not the first person to have been imprisoned there. Eventually he figures out the secret of the maze and realises that all the previous occupants of the maze were also him, and that when each had got as far as he could toward escaping, he used his death to power the teleporter and create a fresh copy of himself from the teleporter's pattern buffer, who would then start exploring all over again. This is followed by a montage showing that in each loop the Doctor gets a bit closer to escaping, until finally he wins free and the episode ends.
• In The Flash episode "Null and Annoyed", Marlize DeVoe realizes that her husband has been drugging her in order to keep her on his side. Fearful, she records a video message to herself with the truth and tries to save it under an innocuous name, only for the computer to notify her that a file with that name already exists. She is shocked to see a message similar to the one she has just recorded telling her to run. Then DeVoe appears and tells her that she always names the video the same way, implying that this trope has happened multiple times and he had to wipe her memory every time. He then proceeds to do it again.
• In an episode of Get Smart, Max gets knocked out in an injury after discovering a big KAOS scheme and a KAOS agent plays a doctor treating him who 'prescribes' instant amnesia pills. Time after time, just as Max is about to remember the scheme, it's time to take a pill, and it's back to square one.
• The second season of The Good Place opens during one of these. Every time the four main humans figure out that they're actually in the Bad Place and being tortured, Michael wipes their memories, forcing them to start from scratch and work out the truth again. They have to go through 802 cycles of this before Michael finally realizes this isn't accomplishing anything.
• In an episode of Mahou Sentai Magiranger, Houka was hit with a spell that caused her to lose her memory every hour, on the hour.
• Monk: In one episode, Monk realizes something he had overlooked about his wife's murder and starts to investigate. After it becomes a dead end, a witness complains that he's been coming by every few years asking the same questions. Apparently he was blocking out the fact that the lead didn't go anywhere.
• Star Trek: The Next Generation: In "Clues", this trope's played with as the crew apparently encounters an unstable wormhole and moves on, only to start finding clues of a missing time period that lead them back to that anomaly for answers. It turns out that they investigated the anomaly before and uncovered a group of xenophobic Sufficiently Advanced Aliens who'd wiped their memories to keep their existence a secret, which created the missing time period. Once the truth's revealed, the crew redoubles its efforts to cover up the events all over again so they won't go through yet another loop, since, if they come back a third time, they almost surely will get killed by the increasingly annoyed aliens.
• Star Trek: Voyager: In "Latent Image", the Doctor has to choose between two patients to operate on because he can only save one. He chooses Harry Kim, a main character, rather than Ahni Jehtal, then has a Heroic BSoD over what he thinks was a Sadistic Choice. To cure him of this, the crew secretly erase his memories of the operation — except the Doctor keeps stumbling upon the evidence, and going into Heroic BSoD all over again. Eventually the crew realizes that they'll just have to leave his memories alone and let him sort it out, even if it's risking a permanent crash.
• In Torchwood, the Retcon pill used by Torchwood Three to invoke Laser-Guided Amnesia can leave fragments of memories triggered by seeing forgotten things/people again. This is a plot point in the pilot where Gwen is made to forget the existence of Torchwood, only to stumble on it again.
• In Westworld, Maeve keeps having what she thinks are dreams, featuring a Westworld staff member in a hazmat suit. When she suspects her memories are being tampered with after Dolores triggers her self-awareness, she quickly sketches the figure in the hazmat suit and goes to hide it under a loose floorboard, only to discover a bundle of similar drawings from when she's done this previously.
  • Turns out to have happened to Jim Delos, who was trying to have a brain scan of him made functional. By the time we see him, it's been going on for many, many years, with the longest amount of time a loop lasting being 31 days.
  • At the end of season 2, the same fate as the one above was set for William, with the same conversation from the first happening. It turned into an Aborted Arc once season 3 came out, with it not even being mentioned and the timeframe between seasons being too short to have it happen.

Tabletop Games

• In the old pre-reboot Mage: The Ascension, this was created by a massive spell cast around the truth of the origin of the Virtual Adepts. It was finally discovered when someone assigned to go over some stolen Technocratic information sat down to read for a few minutes, and discovered he'd been reading for several hours.

Video Games

• In Little Busters!, Komari's memories of her older brother do this - whenever she finally finds out the truth that he died, she falls into a Heroic BSoD so bad that the only way to get out again is to repress the memories...leaving her once more a happy girl curious about dreams of a brother she doesn't know. Riki manages to break her out of the loop by forcing her to accept reality, but Komari's grandmother had a similar thing happen to her and never recovered.
• Planescape: Torment:
  • The story of the Nameless One. Every time he dies and comes back, he forgets everything about his life but then someone notices a Note to Self tattooed on his own back, which instructs him where to start searching for his past... and said search usually ends in his death and amnesia. In the game, you control the umpteen thousandth incarnation.
  • In an in-game short story told by Morte, an amnesiac man is sitting by the side of the road when an old hag appears and asks him for his third (and final) wish. Confused, he asks how he can make a third wish when he hasn't even made a first or second wish yet, and she explains that he already did, but he can't remember them because he used his second wish to undo his first wish. The man is clearly skeptical of the hag's claims, but nevertheless wishes to remember who he is. The hag grants his wish and disappears, cackling. "Funny... that was your first wish." It's heavily implied that this story was inspired by The Nameless One's plight.
• Rengoku: It's heavily implied that being defeated by Gryphus on the last floor also completely resets the ADAM, as floor masters react to Gram as if they've fought countless times already. It's intentional in both games, as in the first game Deucalion awaits an ADAM with enough will to break the cycle, while in the second game Beatrice waits from Gram to recover his memories.
• In Runescape, this is a central plot point in the "Forgiveness of a Chaos Dwarf" quest.
• In the Confusion ending of The Stanley Parable, the Narrator and player find a script in a room describing a timeline of the ending itself. One event says that the Narrator forgets the events that occurred after restarting the game four times. The Narrator is savvy enough to not restart the game this time, but the game restarts on its own, causing him to lose his memory. The player can repeat the steps taken to proceed to the Confusion ending again while the Narrator is none the wiser.

Webcomics

• Casey and Andy: The title characters watch a movie, then decide that they want to be able to enjoy the twists again, so they erase their memories of watching it and watch it again. It later turns out that they had done this around 60 times for that particular movie.
• Defied in Freefall — when Florence gets kidnapped onto a top-secret military base, the commander (who was unaware of the plot) uses direct orders to forbid her from talking about it, instead of a memory wipe, specifically because he knows that anyone with missing memories would try to find out what happened to them.
  Commander: We haven't kept this base secret by being amateurs.

• In Mixed Myth, the sphynx Tamit is actually the Anthropomorphic Personification of Enigma, which means she's destined to always be a mystery to herself. Any time she learns her true identity, she then forgets everything.
• Done humorously in a Penny Arcade: A man wakes up in a field, trying to figure out how he got there ("I was running from...something...") at which point a big monster whacks him over the head. The last panel is identical to the first.

Web Original

• Variation in Kamen Rider Ex Aid Kamen Sentai Gorider. Emu Hojo had to clear a game that was endlessly spawning monsters in the real world, but every time he died in the game, he had to start over with his memories erased. His only saving grace was a Note to Self coded in a Goroawase Number...written in his blood as he died last time.
• Ruby Quest. It's hinted early that it's not the first time You Wake Up in a Room, but the full extent is only revealed near the end: It's been going on for a bloody full year.
• Phelous fell into this during his review of Triangle.
• Tribe Twelve: Milo Asher's journal revealed he had his mind wiped twice by his mother, with both occurrences lasting several years and erasing everything he knew about the Slender Man and his mother's secrets. Each time he eventually re-discovered the journal and all the information within, only for it to happen again.

Western Animation

• On American Dad!, every year Francine brings up the idea of having her parents move closer to them. Every year Stan takes her to a hypnotherapist to wipe the idea from her mind. But then, because he treats the therapist badly, the therapist orders Francine to remember everything.
  • The episode "Father's Daze" has Stan dissatisfied with the Father's Day celebration the rest of the family set up, so Stan erases their memories so they can try Father's Day again. And again. And again and again and again ...
• Kronk on The Emperor's New School does this in order to keep Mudka's Meat Mugs recipe a secret, even from himself despite being the chef, by dropping a grand piano on himself. Hilarious in that the only ingredients in the recipe is salt and pepper.
• Milo Murphy's Law: In "Managing Murphy's Law", the Dakota and Cavendish subplot involves the duo investigating an alien artifact near the local Slushy Dawg. Unfortunately, they keep getting their memories erased by the device and end up repeatedly going through the drive-thru, to the increasing frustration of the cashier.
• An episode of Monsters vs. Aliens (2013) involved the monsters seeing something so horrific and disgusting (Coverton in his chrysalis state) that they purposely erase their memories of it. Then they all wonder why they are mysteriously missing an hour of time and investigate, ending up subjecting themselves to the same sight and erasing their memories again. Then they wonder why they are mysteriously missing two hours of time and investigate again... and again... and again. However, B.O.B. is immune to the memory erasing because he has no brain, and throughout the episode he tries to stop the rest of the monsters from investigating and re-scarring themselves. Eventually he gets so sick of the loop that he destroys the memory erasing device, telling the rest of the monsters that if he has to suffer with the memory of what they saw, then so do the rest of them.
• The Penguins of Madagascar has an episode with Private finding a bottle of "Amnesia Spray".
  Private: Oh, what's this? Amnesia spray! Fantastic! (squeezes the bottle and sprays himself)
  Private: Oh, what's this? Amnesia spray! Fantastic! (squeezes the bottle and sprays himself)
  Private: Oh, what's this? Amnesia spray! Fantastic! (Hesitates and holds the bottle away)
• On The Venture Brothers, in the fourth season, Hank and Dean keep discovering that SPHINX's secret base is in an annex of the Venture compound, and Brock keeps having to erase their memories. After a while, Brock gives up because it isn't worth the effort and it seems to be giving the boys some wacky brain damage where they can't properly describe the color pink.
  Hank: It's kind of a... "Wednesday" color?

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