History Main / SanitySlippage

* Wrestling/RandyOrton infamously started to lose it after his first world title run, which involved his friend and mentor, Wrestling/TripleH, ousting him ([[NoHoldsBarredBeatdown forcefully]]) from Wrestling/{{Evolution}} in a fit of jealousy. Cracks began to show in The Legend Killer's suave persona over the next few years, and a Wrestlemania feud with (and loss to) Wrestling/TheUndertaker shoved him over the deep end.

-->-- '''ComicBook/TheJoker''', ''Film/TheDarkKnight''

* Very subtly done with James Ironwood in ''WebAnimation/{{RWBY}}''. When he's introduced, he's portrayed as an apparently decent man who nonetheless thinks his military is the best solution to everything, even when it's pointed out that it intimidates people instead of reassuring them. He also acknowledges early on that it's possible to see things that aren't there even after a battle ends, with the implication that he himself suffers PTSD. Then his robot soldiers are hacked, the city he's guarding is invaded, and TheDragon of TheBigBad puts out a big speech implying every kingdom is secretly on the brink of war. Every appearance since then, James has been shown trying to gain more control of the situation by making decisions that increasingly ignore anybody else's opinions and observations, while hiding his own doubts behind a mask of seemingly rational calm... right up until he snaps at the end of volume seven, decides to abandon the planet, and orders the heroes arrested for pointing out how that doesn't save anyone.

* Taken to the extreme in ''VisualNovel/DanganronpaV3KillingHarmony'' where Chapter 6 reveals that Danganronpa is a reality show where people crave for the murders and bloodlust and how Shuichi, maki and Himiko;s personalities, pasts and everything are nothing but fabrications and lies, This caused Shuichi to completely lose his mind.

* In ''WesternAnimation/TheSpongeBobMovieSpongeOutOfWater'', ''everyone'' in Bikini Bottom loses it after the formula is stolen, becoming savage and selfish. Sandy is a more noticeable example, as her treedome is converted into a RoomFullOfCrazy, and she keeps prophesying about [[TheEndOfTheWorldAsWeKnowIt "The End"]].

A character has been a bit ... off for a while now. Maybe they just [[NotHimself haven't been themselves]], maybe they've gone as far as painting a RoomFullOfCrazy while reciting a MadnessMantra, or maybe they've gone through a MadnessMakeover, but it's apparent from their actions that their rational mind is losing its grip and they are sliding inch by inch toward insanity.

* During the second act of ''VisualNovel/DokiDokiLiteratureClub'', Yuri, who was previously kind of weird but sympathetic and harmless, starts to get increasingly overexcited just from being near the PlayerCharacter. She also rushes off to [[SelfHarm cut herself]] when she gets excited, something she presumably did earlier with much more moderation, and gets openly excited at the gory horror in the book she's reading. [[ReluctantPsycho Though she's afraid of what's happening to her]], she can't help it, and she starts getting aggressive towards the other girls and possessive of the player character. [[spoiler: Perhaps her last flash of sanity is when she feels like vomiting after handing her last [[{{Squick}} "poem"]] to the player character. Finally, she drives everyone else away from the clubroom and confesses her love to the player character with such delightful turns of phrase as "I just want to pull of your skin and crawl inside of you" before going LaughingMad and stabbing herself to death.]] It's later revealed this was because [[spoiler: somebody was affecting her mind to exaggerate aspects of her personality to motivate the player not to choose her to romance.]]

* [[VisualNovel/{{Echo}}]] has a lot of examples. Basically everyone who has their own route end up very messed up. Well, that or [[spoiler:[[VillainProtagonist Chase]].

[[folder:Films -- Animation]]

[[quoteright:316:[[Webcomic/GunnerkriggCourt https://static.tvtropes.org/pmwiki/pub/images/jack_slipping.png]]]

[[quoteright:317:[[Webcomic/GunnerkriggCourt https://static.tvtropes.org/pmwiki/pub/images/Jack_slipping_4748.jpg]]]]
[[caption-width-right:317:Get some sleep, Jack.]]

!!Example Subpages:

!!Other Examples:

[[folder:Films — Animation]]

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* In ''WesternAnimation/TheSecretOfTheMagicPotion'', Sulfurix was never a very stable individual to begin with, but his sanity keeps deteriorating over the course of the film. He seems to completely lose it once he realises that [[spoiler:Getafix did not transmit the full recipe of the Magic Potion to Teleferix]].

* A daily occurrence in ''TabletopGame/{{Warhammer}}'' and ''TabletopGame/{{Warhammer 40000}}''; living in an endlessly terrible CrapsackWorld will do that. Witches/psykers are especially vulnerable to Slippage, thanks to the source of their powers being the home of TheLegionsOfHell.
* Also appears in TabletopGame/WarhammerFantasyRoleplay, it has a mechanic for going insane and lists quite a nice amount of mental illnesses for which your character can suffer
** As befits its source material, GaidenGame ''TabletopGame/DarkHeresy'' has mechanics by which players can go insane.

* ''TabletopGame/TrailOfCthulhu'' iterates on ''Call'''s design with it's sanity/stability split. Sanity is the same as it ever was, but Stability represents how well put together are. Characters with low Stability definitely resemble the slippage, while high Stability allows even an insane cultist to fake normality.
* Everyone in ''TabletopGame/NewWorldOfDarkness'', from normal humans to blood-hungry vampires to reality-bending mages, has a KarmaMeter. As you slide down the slippery slope, you tend to become a little more unstable with each step, until finally, humans are reduced to raving lunatics, vampires and werewolves go nuts and become meat-hungry animals, mages and changelings fly off the deep end and lose the ability to separate reality from fantasy, and prometheans lose hope of ever becoming humans.
* The ''TabletopGame/OldWorldOfDarkness'' also has sanity-slipping {{Karma Meter}}s, though not all splats have them.
* The fan-made ''World of Darkness'' game ''TabletopGame/GeniusTheTransgression'' is unique in that players start out insane by nature of their [[MadScientist profession]], and as they lose Obligation start unconsciously [[RealityWarper altering reality]] to fit their delusions.

* Characters in ''TabletopGame/EclipsePhase'' are very hard to [[DeathIsCheap kill permanently]] due to [[BrainUploading cortical stacks and backups]], fortunately for [[KillerDM GMs]] there's a mechanic called "stress points" that can cause psychological disorders or permanent catatonia if the PC lets them accumulate.

* Blanche in ''Theatre/AStreetcarNamedDesire'' as well as the film adaptation with Creator/VivienLeigh.
* ''Theatre/SweeneyToddTheDemonBarberOfFleetStreet'' does this with its eponymous character via [[SanitySlippageSong "Epiphany"]].

* In ''The Medium'' by Gian-Carlo Menotti, PhonyPsychic Baba suffers increasingly from delusions of someone touching her throat and childlike voices calling out to her as in one of the séances she and Monica put on. She suspects Toby of being the one who touched her, and interrogates him with increasing violence (being a CuteMute, Toby never answers).
* Burr shows shades of this in the song "The World Was Wide Enough" during ''Theatre/{{Hamilton}}''. It's particularly evident in the line "This man will not make an orphan of my daughter!"

* ''VisualNovel/HigurashiWhenTheyCry'' has this occur several times, almost once an arc, and often bloodily.

* ''VisualNovel/TheFruitOfGrisaia'': In her bad ending [[spoiler:Makina goes through this after watching Yuuji die right in front of her. She proceeds to keep his rotting body in a trash bag talking to him, believing he is still alive.]]

* Malikar, the villain of a game ''WebAnimation/PuffinForest'' ran, had a form of ResurrectiveImmortality, being reborn every time he died, but losing the vestiges of his humanity as a consequence.

* ''VisualNovel/{{Grisaia No Kajitsu}}'': In her bad ending [[spoiler:Makina goes through this after watching Yuuji die right in front of her. She proceeds to keep his rotting body in a trash bag talking to him, believing he is still alive.]]

* Wrestling/MickieJames's obsession regarding Wrestling/TrishStratus started about as innocently as an ''obsession'' could conceivably be (she used Trish's moves in new ways, hung around, sung her praises, ect). But then Mickie started giving up her own good fortunes for Trish, first admirably but later...to the detriment of her own health. Then Mickie started dressing like Trish. Then she got ''jealous'' of anyone who spent any significant time Trish, be it Trish's preexisting protege Ashley or Trish's boyfriend Chad. When Mickie basically [[NotWhatItLooksLike rested her head on Trish's crotch]] and [[NoSenseOfPersonalSpace refused to move it]] that was enough for Trish but the descent of Mickie's sanity had only just begun.

* Wrestling/{{Edge}} began to gradually lose his mind as he kept getting closer to a Wrestling/HellInACell match with Wrestling/TheUndertaker. It took Wrestling/MickFoley to tell Edge that he needed to let loose to have a hope of winning, culminating in a two-word WorldOfCardboardSpeech: "I understand."

Compare GoMadFromTheRevelation, FreakOut, VillainousBreakdown, RoomFullOfCrazy, MadnessMantra, LaughingMad, and WithGreatPowerComesGreatInsanity. If this is a backstory it's PreInsanityReveal. Compare SlowlySlippingIntoEvil. The opposite of SanityStrengthening.

->''"Madness, as you know, is like gravity. All it takes is a little '''push'''!"''

* SanitySlippage/WebComics

!!Examples:

* SanitySlippage/{{Film}}

* {{SanitySlippage/Music}}
* SanitySlippage/ProfessionalWrestling

* SanitySlippage/WebOriginal

[[folder:Radio]]
* ''Radio/BleakExpectations'': A few days on a dessert [[note]]Not a typo, it's an island [[ExactlyWhatItSaysOnTheTin made out of dessert]][[/note]] island drive Pip Bin utterly mad, to the extent that he loses track of time, and considers eating himself, only relenting when he realises this is "probably a bit of an own goal". He quickly recovers when he finds someone to boss around.
** PlayedForDrama with Harry Biscuit's mother, who after her husband died started believing she was literally a biscuit (named Susan), and dunked herself to death. After that, the Biscuit fortune was taken by their rivals, the Flapjacks, and Harry was sent to [[BoardingSchoolOfHorrors St. Bastards]].
** Subverted with Pip Bin's own mother, who after the death of her husband starts sitting in linen closets and claiming to be a tablecloth married to a curtain, before moving on to bizarre interior decorating tips (replacing the walls with geese, putting scatter cushions on fire), and then believing she's the host of a cooking show. In Georgian England. Only it turns out [[spoiler:she was faking it, and the minute her husband returns she goes back to normal.]]

[[folder:Tabletop Games]]
* A daily occurrence in ''TabletopGame/{{Warhammer}}'' and ''TabletopGame/{{Warhammer 40000}}''; living in an endlessly terrible CrapsackWorld will do that. Witches/psykers are especially vulnerable to Slippage, thanks to the source of their powers being the home of TheLegionsOfHell.
* Also appears in TabletopGame/WarhammerFantasyRoleplay, it has a mechanic for going insane and lists quite a nice amount of mental illnesses for which your character can suffer
** As befits its source material, GaidenGame ''TabletopGame/DarkHeresy'' has mechanics by which players can go insane.
* ''TabletopGame/CallOfCthulhu'' is famous for introducing the SAN attribute, which drops a little each time the players encounter a monster or cast a spell, or something.
** Mechanically, most Mythos creatures and knowledge cause a San check. A failed check will generally make you roll, while a successful check will only deal one point. Most lesser mythos creatures can only inflict up to the max Sanity damage that roll can deal to a person before the character becomes ConditionedToAcceptHorror. This also adds to a characters Mythos Knowledge score, which is subtracted from their maximum possible sanity (not to be confused with their current SAN score)
* ''TabletopGame/TrailOfCthulhu'' iterates on ''Call'''s design with it's sanity/stability split. Sanity is the same as it ever was, but Stability represents how well put together are. Characters with low Stability definitely resemble the slippage, while high Stability allows even an insane cultist to fake normality.
* Everyone in ''TabletopGame/NewWorldOfDarkness'', from normal humans to blood-hungry vampires to reality-bending mages, has a KarmaMeter. As you slide down the slippery slope, you tend to become a little more unstable with each step, until finally, humans are reduced to raving lunatics, vampires and werewolves go nuts and become meat-hungry animals, mages and changelings fly off the deep end and lose the ability to separate reality from fantasy, and prometheans lose hope of ever becoming humans.
* The ''TabletopGame/OldWorldOfDarkness'' also has sanity-slipping {{Karma Meter}}s, though not all splats have them.
* The fan-made ''World of Darkness'' game ''TabletopGame/GeniusTheTransgression'' is unique in that players start out insane by nature of their [[MadScientist profession]], and as they lose Obligation start unconsciously [[RealityWarper altering reality]] to fit their delusions.
* ''TabletopGame/{{Exalted}}'' loves this trope:
** The Solars gradually experience this as they become more and more godlike, from both the Great Curse and general detachment from humanity and less powerful divine beings.
** Being close to a Primordial War survivor in the First Age can be dangerous, humiliating, and bad for your physical, mental, and social health.
** Also happens to Infernals. They have access to Yozi Charms. Everything the Yozis are, is made of Charms. Most of the Yozis are insane, and their Charmsets tend to be arranged so that the good stuff with no drawbacks is padlocked by something with benefits that makes you a little crazier. The best example of this is Kimbery, who has an entire Charm tree (built on ThePowerOfHate) locked behind something that permanently skews the sanity of its user to be either more naive or more vindictive, depending on the chosen variant.
* In ''TabletopGame/FadingSuns'', Psychics and Theurgists are prone to "Urge" and "Hubris" respectively.
* Characters in ''TabletopGame/EclipsePhase'' are very hard to [[DeathIsCheap kill permanently]] due to [[BrainUploading cortical stacks and backups]], fortunately for [[KillerDM GMs]] there's a mechanic called "stress points" that can cause psychological disorders or permanent catatonia if the PC lets them accumulate.
* Any KillerGameMaster worth the title can put this into ''any'' game.

[[folder:Theatre]]
* Blanche in ''Theatre/AStreetcarNamedDesire'' as well as the film adaptation with Creator/VivienLeigh.
* ''Theatre/SweeneyToddTheDemonBarberOfFleetStreet'' does this with its eponymous character via [[SanitySlippageSong "Epiphany"]].
* The title characters in Creator/WilliamShakespeare's ''Theatre/{{Macbeth}}'' and ''Theatre/{{Hamlet}}'' gets an obsessive variety.
* The title character of ''Theatre/ThePhantomOfTheOpera'', though your mileage may vary on how sane he was to begin with. But he's definitely completely off the beam by the end, determined to have Christine at all costs, even if he has to blackmail her into marriage by threatening to kill her lover.
* In ''Theatre/ShrekTheMusical'', Fiona has a moment of this in "I Know It's Today" from waiting to be rescued [[GoMadFromTheIsolation from a small room in a tower for over twenty years]].
* In ''The Medium'' by Gian-Carlo Menotti, PhonyPsychic Baba suffers increasingly from delusions of someone touching her throat and childlike voices calling out to her as in one of the séances she and Monica put on. She suspects Toby of being the one who touched her, and interrogates him with increasing violence (being a CuteMute, Toby never answers).
* Burr shows shades of this in the song "The World Was Wide Enough" during ''Theatre/{{Hamilton}}''. It's particularly evident in the line "This man will not make an orphan of my daughter!"

[[folder:Visual Novels]]
* Sakura in ''VisualNovel/FateStayNight''. It's like everything anyone ever says to her is another stab at her self confidence. And then Shinji tries [[spoiler:to rape her one more time, and then he'll tell Shirou about it]]. Yeahhhh things kind of go downhill from there. Oh, and she was already [[spoiler:eating people in her sleep]], passing out frequently and also quietly going crazy anyway. [[spoiler:She does get better, however.]]
* ''VisualNovel/NineHoursNinePersonsNineDoors'' has [[spoiler: Clover, waking up and being forced into playing the Nonary Game. For a second time. She is fine over this. What gives her a dive in the deep end, is Snake's death. Apparent in the "[[MultipleEndings Axe]]" ending]].
* ''VisualNovel/HigurashiWhenTheyCry'' has this occur several times, almost once an arc, and often bloodily.
* The [[Franchise/WhenTheyCry sister series]], ''VisualNovel/UminekoWhenTheyCry'', reveals in the fifth arc that [[spoiler:Natsuhi]] has slowly been losing it since [[spoiler:Kinzo died]] ''two years'' before the story begins.
** Arc 3 of ''Umineko'' also has [[spoiler:Eva/Eva-Beatrice]] ''really'' losing it, first after [[spoiler:finding the gold]] and then after [[spoiler:Hideyoshi is killed]]. By the end of the arc, she's gone completely [[AxCrazy apeshit]] and [[spoiler:shoots Battler]].
* ''VisualNovel/{{Grisaia No Kajitsu}}'': In her bad ending [[spoiler:Makina goes through this after watching Yuuji die right in front of her. She proceeds to keep his rotting body in a trash bag talking to him, believing he is still alive.]]

->'''Steven:''' It wasn't that important, you guys! You're making a big deal out of ''nothing!'' Have I done some things wrong? Sure! I trashed a house today, I broke an anvil - what teenager hasn't?! Dad and I had a little disagreement, that's practically a rite of passage! I mean, it would be weird if we didn't, right?! And maaaaybe I've had a not-so-nice thought or two about, like, y'know, [[spoiler: ''slamming White Diamond's head through a pillar'']], but it's not like I actually went through with it! ''(laughs)'' I only actually [[spoiler: [[WhamLine shattered Jasper]]!]]\\
''(everyone gasps in shock, Pearl screams)''\\
'''Amethyst:''' '''''[[BigWhat WHAT?!]]'''''\\
'''Connie:''' You're joking, right?!\\
'''Steven:''' Oh, don't worry! I fixed that too! I can fix ''anything''! I can just keep messing up and fixing things forever, and you'll never have to know about ANY of it!\\
'''Garnet:''' ''(horrified)'' Steven...\\
'''Steven:''' ''(gasps; angry)'' How messed up is that...? That I've gotten away with this for ''so long''... You have NO IDEA how bad I am! You think I'm so great, and I'm so mature, and I always know what to do, but THAT'S NOT TRUE! I haven't learned a thing from my problems! They've all just made me worse! You think of me as some ''angel'', but I'M NOT THAT KID ANYMORE! ...I'm a fraud... ''(collapses to his knees, heavy breathing)'' I'm a fraud... ''(grabs his head, shaking)'' '''I'M A MONSTER!''' [[spoiler: ''([[WhamShot spikes burst out of his back]], [[{{Cliffhanger}} episode ends]])'']]
-->-- ''WesternAnimation/StevenUniverseFuture''