This trope is about characters with a form of Involuntary Shapeshifting or Super-Powered 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, though characters with a Jekyll And Hyde style Split Personality, Demonic Possession, 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 carcassesnote .
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 Bad Dreams 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.
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 also Identity Amnesia and Amnesiac Dissonance.
This is probably the most "realistic" presentation of 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.
- 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 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.
- 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.
- Wolf Man Shishido Shirou/Shiho from My Monster Secret transforms from male to female whenever he/she looks at the moon (or a picture of the moon). Male Shirou suffers from this as he's typically asleep whenever female Shiho is in control of their body, while Shiho herself doesn't have this problem.
- Played with in Kara no Kyoukai: 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.
- Zigzagged with the Incredible Hulk 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.
- This is how the first Cheetah (Priscilla Rich) expressed her multiple identities, 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.
- 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).
- Rose and Thorn of The DCU. In The Golden Age of Comic Books you had a standard Jekyll & Hyde case. At first Thorn was an enemy of the Jay Garrick Flash, and after being cured of Thorn, Rose became the wife of the original Green Lantern. Too bad it couldn't last; Thorn resurfaced and Rose had to stop her for good with a Heroic Sacrifice. In the modern era, Post-Crisis Rose and Thorn are another story. Thorn is a Badass Normal superhero initially out to bring the gang that her/their police officer father died against to justice. Each knows the other exists, but don't remember what the other did while in charge, so they have to write to each other.
- Robin Series: 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.
- 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.
- In Carry On Screaming!, this happens to Sergeant Bung after he is fed the Mr. Hyde serum.
- 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 protagonist in Fight Club doesn't remember any of his alter-ego's activities.
- In Werewolf: The Beast Among Us the werewolf's human persona is completely unaware of their full moon activities and has been since birth.
- 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 before 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").
- Averted by Angua von Überwald in the Discworld. She remembers perfectly well what she was doing in her wolf-form, especially when on police work. The only difficulty she has is vocabulary, so as to report it accurately in a way that makes sense. Human speech is geared to visual metaphors. As sight is our dominant sense you'd expect this: our visual vocabulary is rich and extensive. But smell, rather than sight, is dominant in canines. A werewolf interprets the world through her nose. And human speech has a very impoverished olfactory vocabulary. The nearest Angua can get is to explain in terms of synasthaesia - blood and violence smell red, sex smells blue-purple, and so on. Which still only conveys a thousandth part of her nasal experience, especially in a city as odour-rich as Ankh-Morpork.
- 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.
- Averted in A Wolf In The Soul. Greg remembers everything he does as a wolf, which is the only reason he has a fighting chance.
- 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 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.
- 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.
- Ujurak from Seeker Bears forgets he's a bear when he's in another form.
- Heroes: Nikki is like this when her Jessica first starts taking over her body.
- 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.
- 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 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.
- 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.
- Red Riding Hood in Once Upon a Time suffers from this regarding their werewolf transformations and murders.
- Werewolves in Supernatural suffer memory blackouts when they transform.
- Teen Wolf:
- The Kanima in season two has no memories of what they do when transformed, in contrast to the actual werewolves who have perfect control and recall during their changes.
- In season 3, Stiles is possessed and appears to have no knowledge of what he does when the thing possessing him takes control.
- At the end of the Buffy the Vampire Slayer episode "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 the other students displayed amnesia, and Xander admits he just doesn't want to talk (or think) about it.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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".
- One blink-and-you'll-miss-it line in Boktai 2: Solar Boy Django states this is a drawback to using his Super-Powered Evil Side along with losing control of his actions. Not that this affects the game in any way.
- Exploited in Danganronpa: Trigger Happy Havoc. Touko Fukawa and Genocider Syo both have this, but when their shared body is hit with a dose of Laser-Guided Amnesia, only the active personality was affected. This means one of them remembers The Worst, Most Despair-inducing Incident in the History of Mankind — unfortunately, they're unable to provide any concrete details, as it was the other who actually experienced it.
- 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.
- Owen, the hidden fourth personality within Uendo Toneido in Phoenix Wright: Ace Attorney Spirit of Justice. Similar to the above, only 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.
- 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.
- 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.
- This amnesia has been useful to Agatha though, allowing her to build a device to project a message to the world (or at least a localised part of it) that she has been possessed and that people should aid the Baron. The Manipulative Editing that follows and completely reverses the meaning of her message is more the fault of Tarvek than Lucrezia.
- Hank doesn't remember the actions of her werewolf form in The Night Belongs To Us.
- The Adventure Time episode "Hug Wolf" has Finn becoming the said 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! had an episode in which 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 unconciously 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.
- Mr. Bogus apparently suffered from this in the first act of the episode "Nightmare On Bogus Street". After Bogus became 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.
- In a Legion of Super-Heroes 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.