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* ''Literature/TwentySixSixtySix'':
** Amalfitano, though it’s implied to happen to people who stay in Santa Teresa for too long. Being caught up in UsefulNotes/WorldWarII doesn't help matters, either.
** Espinoza [[spoiler: eventually becomes enamored with a local girl and nearly forgets about the search for Archimboldi.]]
** Sammer [[spoiler: goes from running a quaint European town to ordering the deaths of hundreds of people.]]
** Entrescu [[spoiler: gets desperate enough to take refuge in Dracula's castle and is eventually crucified by his own men.]]
* In ''Literature/TheAffix'' Matt is driven off the rails a bit by the sheer inanity of his circumstances: saddled with a gem that [[WeirdnessMagnet blows up probability]] and [[ClingyMacGuffin won't let him get rid of it]], accosted constantly by dangerous believers in the supernatural that he thinks are crazy, and perpetually short on sleep. After a day or so of this he gives up on trying to make much sense of it and gets openly hostile towards his antagonists, and as a result he becomes fairly dangerous in his own right.
* ''Literature/Alice2014'': Christopher, given that the story is told in third-person limited from his point of view and thus making him the most noticeable. In the beginning he reacts to things the way a normal person would, by freaking out and/or questioning how certain things are even possible. The more he loses his grip on reality, the less he questions how the world around him works.
* In ''Literature/AndThenThereWereNone'', Vera Claythorne becomes increasingly consumed by paranoia and guilt and is so psychologically broken by the end of the book that [[spoiler:she willingly hangs herself with the noose the killer sets up for her]].
* Dr. Seward in his appearance in ''Literature/AnnoDracula''. You have to give him a little insanity though; it's an AlternateHistory of ''Literature/{{Dracula}}'' where instead of the EarnYourHappyEnding situation of rescuing Britain from a supernatural evil while losing (only) your fiancée and an American friend, he lives through a {{Diabolus Ex|Machina}} Kill 'Em [[TheVirus Or Corrupt 'Em]] scenario.
* ''Literature/BlackTideRising'': In ''Under a Graveyard Sky'', Faith goes a little into this after they board a yacht that was taken over by the mercenaries hired to protect it and sees the carnage that followed, [[spoiler:killing and rape everyone there.]] It becomes more serious when they're clearing a [[spoiler:cruise]] ship later. Oddly it's not fighting zombies that does it but what she finds after the zombies are cleared out, [[spoiler:the horror shows in the cabins, even the ones where they find survivors.]] She turns Trixie, a teddy bear they found on one ship into a CompanionCube as a coping mechanism.
* Jaimy in the ''Literature/BloodyJack'' series. Early in ''My Bonny Light Horseman'', he receives a head wound in battle that doesn't get treated for weeks because he's in a French prison. As the series progresses, you can see him slowly spiraling down to his HeroicBSOD in ''The Mark of the Golden Dragon''.
* Duane Hoover in Creator/KurtVonnegut's ''Literature/BreakfastOfChampions'' gradually loses his sanity throughout the novel and is pushed over the edge when [[spoiler: he takes a Kilgore Trout short story as the truth and believes he is the only real person on Earth]].
* ''Literature/BulldogDrummond'' series: Irma, the BigBad Peterson's DarkMistress, goes off the edge completely after [[spoiler:Peterson dies. She talks to a bust of Peterson,]] and even some of her henchmen doubt whether it was a good idea to continue with her.
%%* Lydia in ''Caught In The Act''.
%%* Alfred Lambert in ''Literature/TheCorrections''.
* ''Literature/TheDarkTower'': Roland goes through this in the first third or so of ''Literature/TheWasteLands'' due to [[spoiler:the paradox he created by preventing Jake's (first) death in ''Literature/TheDrawingOfTheThree''. He gets better after being reunited with Jake.]]
* In ''Dead City'' by Shane Stevens, mob enforcer Charley Flowers threatens Scottini's wife in order to find her missing husband's location. He grabs a blanketed pillow from her baby's crib, claims it's her actual child, dangles it out of the apartment window, and drops it after she refuses to cooperate. After Flowers hands her still very well-alive baby in her hands, Scottini's wife - in a shocked daze - gives up her husband's hiding spot after one last threat from Flowers. Nonetheless, [[spoiler:she has a severe mental breakdown believing her baby was truly thrown out of the window. Hallucinating her actual baby in her arms as an inanimate doll, she bashes her own child to a bloody pulp in an insane trance before throwing herself out the window]].
* In ''Literature/DiaryOfAMadman'', the eponymous diary details the descent of Poprishchin into madness, starting with his delusion that [[SpeaksFluentAnimal he can understand dogs and their letters.]]
* ''Literature/{{Discworld}}'':
** The Bursar of Unseen University used to be quite sane, up until the appointment of Mustrum Ridcully to Archchancellor wore away at his nerves. His sanity ''really'' took a dive in ''Literature/ReaperMan'', when ancient wizard Windle Poons rose from the grave. In fact, it's so bad that the medication he's given is specially designed to make him ''hallucinate sanity''.
** In ''Literature/MakingMoney'', Cosmo Lavish was not particularly stable to begin with, but his mental health deteriorates noticeably over the course of the story, [[spoiler:mainly because of his being poisoned by a finger that began to rot after he decided to keep a ring too small on it]]. The man starts trying to understand how [[MagnificentBastard Vetinari]] thinks, and ends up [[spoiler:committed to an asylum for [[NapoleonDelusion people who think they are Vetinari]]]].
* In ''Literature/DontLookBack'', Sam fears this is happening to her when she keeps seeing hallucinations of Cassie and glimpses of her memories; undergoing such an episode in public causes her to be dubbed "Insanity Sam" by her own former friends Veronica and Candy. [[spoiler:Her fear is intensified when she finds out she was the one writing the warning notes to herself, as she apparently wrote them during her brief moments of recalling her memories.]]
* In the original ''Literature/{{Dracula}}'', Jonathan Harker and Renfield experienced this thanks to the Count. Harker recovered; Renfield, not so much. Renfield started out as a mental patient with a fixation on eating life. Dracula makes him considerably ''worse'', but Renfield does recover enough to try and save Mina from Dracula [[spoiler: though he's killed for his trouble]].
* In ''Literature/DragonBones'', Ward's mother is already a {{Cloudcuckoolander}} at the start of the novel, but gets worse over the course of it. In the end [[spoiler: Ward can't find her anymore with his magical ability to find people, even though her body is there.]] She's gentle and nice the whole time, but lives in a world of her own making, and refuses to acknowledge the reality (which is not really worth living in, at least before the death of her abusive husband).
* In the ''Literature/DreambloodDuology'', part of a Gatherer's disintegration towards becoming a [[OurVampiresAreDifferent Reaper]] is losing their mind. Ehiru has violent thoughts and dreams while suffering from dreamblood withdrawal.
* The titular character in ''Literature/EdenGreen'' considers herself a rationalist, but as she investigates the alien needle symbiote infesting the body of her best friend, her grasp on reality gradually begins to slip.
* ''Literature/EmperorMolluskVersusTheSinisterBrain'': Every member of the Council of Egos who survived the [[BrainInAJar conversion process]] all show some level of psychological instability, something implied to be a side-effect of the process itself. In particular, Creator/JaneAusten was left catatonic while UsefulNotes/MarieCurie became a rabid beast the Council uses as their personal attack-dog.
* ''Literature/GoToSleepAJeffTheKillerRewrite'': Jeff not moving on from his grief over Ben's death leads to his fights with Randy and spending months in hospital. The doctor notices possible signs of Jeff's mental decline, which he suspects is due to head trauma. Although his parents do keep Jeff at home to wait for his mental state to stabilise, they overlook signs like his oddly joyous reaction to his new face and his manic smile as he carves a jack-o-lantern's grin. It all comes to a head when Jeff [[MurderInTheFamily murders his family]] in the twisted logic of sparing them from "liv[ing] in this sick and terrible world".
* ''Franchise/HarryPotter''
** Happens to Ron in ''Literature/{{Harry Potter and the Deathly Hallows}}'', whenever he wears the locket.
** Poor Sirius was showing signs of this even before he got put into Azkaban, with his LaughingMad display after [[spoiler:Peter framed him and escaped]]. ''[[Literature/HarryPotterAndThePrisonerOfAzkaban Prisoner of Azkaban]]'' proves his time in the wizarding prison did him no favors, and while he started to recover during ''[[Literature/HarryPotterAndTheGobletOfFire Goblet of Fire]]'' after being put under house arrest for his own protection in ''[[Literature/HarryPotterAndTheOrderOfThePhoenix Order of the Phoenix]]'' he starts slowly slipping again.
** In ''Literature/HarryPotterAndThePhilosophersStone'', Vernon Dursley slowly starts to lose his grip on things as more and more Hogwarts acceptance letters arrive for Harry Potter, nailing up the mail lot, tossing letters in the fireplace and eventually taking the whole family to a deserted island in the middle of a terrible storm in the hopes of getting away. In the film, you can even see that his normally carefully-maintained hair now looks wild.
-->'''Dudley''': Daddy's gone mad, hasn't he?!
* The BigBad of the ''Literature/HeraldsOfValdemar'' series suffers steadily worsening sanity as he {{Body Surf}}s through the centuries, as a result of spending his time between bodies in a SoulJar in the VoidBetweenTheWorlds. As Ma'ar and [[Literature/LastHeraldMageTrilogy Leareth]] he's a fairly MagnificentBastard, but by the time we see him as Mornelith Falconsbane in the ''Winds'' trilogy he's grabbed the VillainBall tight and won't let go. The slippage accelerates when he's flung into the Void bodily between ''Winds of Change'' and ''Winds of Fury'', leading to his final downfall.
* Johnny Truant and Zampano in ''Literature/HouseOfLeaves''.
* Katniss Everdeen progressively starts to lose it over the course of ''Literature/TheHungerGames'' trilogy.
* Alicia [=DeVries=] of ''Literature/InFuryBorn'' suffers this throughout the second half of the book due to [[DemonicPossession being possessed]] [[LastOfHisKind by the last of]] [[Myth/ClassicalMythology the Greek Furies]]. Culminates when she discovers the identities of the [[TheMole traitors]] within [[spoiler: the [[TheEmpire Imperial]] [[StandardSciFiFleet Fleet]]]], and subsequently goes [[RoaringRampageOfRevenge batshit crazy]]. Fortunately, she is [[IKnowYoureInThereSomewhereFight stopped]] [[spoiler: [[MoralEventHorizon from ramming a space station with nine thousand innocents]] and the BigBad aboard]] by the Fury and her [[SapientShip ship's AI]] in a BattleInTheCenterOfTheMind.
* A consequence of syphilis in ''Literature/KingdomOfLittleWounds''. The queen has probably been losing her mind for years, and she only appears to get worse over the story.
%%* Jack Merridew and Roger in ''Literature/LordOfTheFlies''.
* Gollum and Denethor in ''Literature/TheLordOfTheRings''. Also, Isildur after he gets the Ring. Boromir, particularly after Lórien.
* Very common in Creator/HPLovecraft's work, most notably in "Literature/TheRatsInTheWalls" and "Literature/TheShadowOverInnsmouth". Of course, considering the [[CosmicHorrorStory type]] of stories he wrote, it's understandable. (Although both of those are actually feature a less cosmic form of horror, with the respective protagonists each finding something unpleasant wiggling in the roots of his family tree.)
* ''Literature/TheLuminousDead'': Gyre becomes an UnreliableNarrator over weeks of [[GoMadFromTheIsolation solitude]], claustrophobia, and dangerously limited supplies as she explores a cave system that's killed dozens of earlier cavers. Worse, she ''knows'' her mind's going, but can't always tell what is and isn't real.
* In Max Barry's ''Literature/MachineMan'', the main character, Dr. Charles Neumann, suffers from this. While not quite "normal" to begin with, after [[spoiler: he's replaced both legs and one hand with Better Parts, he starts talking to them and referring to himself as "we"]].
* In ''Literature/TheMagicians'', this is a common response of students to the fourth year at [[WizardingSchool Brakebills]], for a variety of reasons: first of all, they're studying in Antarctica this year, and the monotony of the landscape can be mind-numbing; secondly, they've been magically prevented from speaking or communicating, driving some to almost GoMadFromTheIsolation; thirdly, the learning process itself is a sanity-shredding series of WaxOnWaxOff exercises designed to internalize the {{Magic Prerequisite}}s, and presided over by a SadistTeacher. As such, several students just snap and start randomly fucking each other in public, so desperate for any kind of human contact that they no longer care who sees them. Meanwhile, Quentin loses his grip on the passage of time and starts hallucinating at length, even resorting to talking to absent friends during [[UltimateFinalExam the marathon to the South Pole]]. Fortunately, most recover quite ready upon returning to the main campus.
* The narrator from ''Literature/TheMothDiaries''. Possibly.
* In the ''Literature/{{Newsflesh}}'' series, Shaun has a bad case of slippage after [[spoiler:being forced to shoot his sister when she's going into amplification, i.e. becoming a zombie]] at the end of the first book, ''Feed''. Over the course of the next two, ''Deadline'' and ''Blackout'', he goes from having conversations with [[spoiler:Georgia]] to outright visual and tactile hallucinations. He's well aware he's clinically insane, and prefers it to sanity, since dealing with the reality of his situation would push him to suicide.
* Happens to a few characters in ''Literature/ThePaleKing'', most notably David Cusk and [[spoiler: Lane Dean]].
* Most ''Literature/{{Redwall}}'' books have at least one villainous character go through this.
* Everyone in ''Literature/TheRepublicOfTrees'':
** Alex: [[spoiler: becoming a PsychoForHire for whoever holds the power -- though truth be told, he just needed a little push ]]
** Isobel: [[spoiler: completely breaking down from Joy's MindRape -- which we get to read in painful detail... except the "therapy reports" are written completely in newspeak.]]
** Louis: [[spoiler: getting more and more lost in his vision of the Revolution, overlooking obvious flaws until everything collapses around him ]]
** Joy: [[spoiler: a meek girl with self-image problems, using her intelligence to get to power and ending a KnightTemplar. Then she realises that she could actually have a boyfriend and it drives her completely {{Yandere}} over a couple of chapters.]]
** Michael, the most notable, being the narrator: over a couple of chapters [[spoiler: he suffers severe head trauma, discovers alcohol, discovers that the girl of his dreams is a slut and what's worse, she only started an affair with him to get back at his brother... he starts hearing voices, having memory gaps...]] By the end of the story he is so broken, that when he discovers what [[spoiler: he is now a boyfriend to a {{Yandere}} and they just murdered his ex in cold blood ]], he decides to just roll with it.
* Brad Cohen of ''Literature/{{Repeat}}'' spends most of the story stuck reliving his entire life on a loop; with this in mind, it's not so surprising that [[TimeLoopFatigue he starts cracking up the longer the loop continues]], at first merely [[WhoWantsToLiveForever feeling isolated to his loop-induced immortality]], then descending into mindless hedonism, then randomly [[NakedNutter taking off all his clothes]] and screaming at the sky. By the end, he's been so frazzled by the endless cycle of rebirth that he has started getting his various lives muddled up, showing up to work at jobs he isn't employed at, forgetting encounters he's already had in his current life... it's not pleasant.
* Jack Torrance in ''Literature/TheShining''. Creator/StephenKing stated his book was about a normal man who goes crazy, and that Creator/StanleyKubrick's [[Film/TheShining film]] was about [[Creator/JackNicholson a crazy man]] [[AxCrazy who goes absolutely bonkers]].
** Louis Creed in ''Literature/PetSematary''. Quite understandable since he's lost his son, brought him back to life, was forced to kill him again, [[spoiler:and repeats the process with his dead wife]].
** Stephen King loves this trope. ''Literature/BagOfBones'' and the short story "The Ballad of the Flexible Bullet" are about men who clawed their way back from the brink of insanity. The short story "[[Literature/SkeletonCrew The Jaunt]]" is about a teleportation machine that causes insanity if it is used incorrectly.
* ''Literature/ASongOfIceAndFire'':
** Theon's PointOfView chapters in ''A Clash of Kings'' show him becoming increasingly more terrified and paranoid, making ever more desperate decisions as he realizes that the reinforcements he needs aren't forthcoming.
** While [[spoiler:Cersei]] had never been completely grounded, she wasn't completely off her rocker either. Over the course of the fourth book, though, in response to [[spoiler: the [[DiedInYourArmsTonight death]] of her [[ParentalFavoritism firstborn]] [[MyBelovedSmother son]] and shortly afterward her father as well]], she starts losing it, seeing enemies in every corner and ordering people [[ColdBloodedTorture tortured]] willy-nilly.
** Arya Stark becomes more and more unhinged after her situation just keeps getting worse with no end in sight.
** Catelyn Stark has a weird variation of this. Early in the first book, she goes into a borderline-psychotic state after major trauma, deeply disturbing everyone around her. She quickly snaps out of it, and from that point on seems okay, but her POV chapters show her becoming increasingly depressed and revenge-driven. She finally snaps when [[spoiler:she watches her firstborn son murdered in front of her eyes, which drives her completely insane, shortly before she's murdered herself. When she's brought BackFromTheDead, it's... [[CameBackWrong not pretty]].]]
* ''Franchise/StarWarsLegends'':
** In the ''Literature/XWingSeries'' Lara Notsil, AKA the former Imperial agent Gara Petothel, slowly goes through one as she [[BecomingTheMask becomes the mask]] after infiltrating Wraith Squadron. It turns out that Imperial Intelligence was... ''[[{{Understatement}} lax]]'' in concerning themselves with what would happen to an agent after having so many different identities swirling around in their head. She manages to never show it, but some of her inner dialogue is downright depressing as she fights between her two[[spoiler: /three]] different identities in order to stay with her Squadron.
** Palpatine from ''ComicBook/DarkEmpire''. Pre-Endor Palpatine had been scarily sane, but the ordeals of death, {{Body Surf}}ing, and the natural mental instability of clones leads him further down the slope throughout the course of the story.
** In Creator/TimothyZahn's ''[[Literature/TheThrawnTrilogy Thrawn Trilogy]]'', Joruus C'Baoth was always insane, but generally did a good job keeping that fact concealed. His control slips drastically by ''The Last Command''.
* ''Literature/TheStormAravDagli'': A miserable marriage has led the wife to attempt her own life many times, and the decision to kill her husband to end [[LoveMartyr her love for him despite his abuse]] gives her a newfound resolve. Once she's done the deed and watches him bleed out, she barely realises the blood she rubs on her face as she begins to smile and laugh. As the moonlight shines on her, she's described to deteriorate into something less than human.
* ''Literature/TheStormlightArchive'':
** Szeth-son-son-Vallano is a pacifist who is also a Truthless -- a sort of warrior-slave of his people, bound to obey anyone who holds his Oathstone. He is also [[OneManArmy quite possibly literally the most dangerous man on the planet]], partly because he's the first [[DifferentlyPoweredIndividual Surgebinder]] to be seen in four thousand years. He, understandably, is typically used as a weapon and assassin, which is made worse by the fact that there is nothing magical about his oath; he could stop the murders at any moment [[ToBeLawfulOrGood if he would just choose what is right over the law]]. By [[Literature/WordsOfRadiance the second book]], his brain is barely hanging on by a thread. It gets worse [[spoiler:when he finds out that the "lies" he told that got him made Truthless were actually true all along, meaning absolutely ''none'' of it was necessary]].
** The Heralds, who have been wandering the world for four thousand years after giving up on their oaths, are getting crazier. Shalash (Herald of Beauty) has taken to destroying any artwork depicting her, Nale (Herald of Justice) is obsessed with law to the point of being willing to kill a girl over petty theft--but stopping the instant she is pardoned, and Kalak has become a paranoid wreck jumping at shadows.
--->'''Kalak:''' I'm worried about Ash.\\
'''Nale:''' You're worried about everything.\\
'''Kalak:''' She's getting worse. We weren't supposed to get worse. Am I getting worse? I think I feel worse.
** Elaborating on Nale, he's seen the same signs of [[spoiler:the upcoming Desolation]] Szeth did, but refuses to believe them, and his sanity is suffering as a result of him trying to [[BelievingTheirOwnLies believe his own lies]].
* ''Literature/{{Stravaganza}}'': Over the course of books five and six, ''City of Ships'' and ''City of Swords'', Grand Duke Fabrizio di Chimici, the main antagonist, starts to suffer this. Of course, his beloved younger sister running away and eventually marrying a member of the family the di Chimicis are archenemies with, and things just generally going wrong on a regular basis, doesn't help.
* In ''Literature/ASymphonyOfEternity'', one of the main characters, Metternich per Pelasgiamus, after a hellish fleet battle debriefs his commander Field Marshall Cornelia. The Field Marshall informs him that because he won the battle and captured the enemies leading Admiral had made the enemy retreat to their strongest [[ThatsNoMoon Space Fortress]] and their predominant strategy was to draw the out makes Metternich's huge victory actually detrimental to their cause. Combined with the fact that this particular fight was a very hard one in which his force of about 350 ships somehow defeated and captured a foe that numbered 18,000 ships makes him almost crack from madness and [[ImagineSpot he imagines jumping over the Field Marshall's desk, strangling her and bashing her head into the floor until it becomes a puddle of goo]]. What's even more disturbing is the fact that he's not a professional soldier, [[BewareTheNiceOnes rather he's a civilian potions maker who was forcefully drafted into the war and is quite polite, charming and funny to those around him]]. [[HeWhoFightsMonsters Though the war is taking its toll on him.]]
* In ''Literature/ThereseRaquin'', the more time passes, the more Thérèse and Laurent are haunted by memories of Camille, and the crazier they become.
* ''Literature/TheseBrokenStars'': As [[{{Socialite}} Lilac]] struggles to keep up with [[MajorlyAwesome Tarver]] through the forest, she starts to hear voices. These voices soon turn to visions, then premonitions. Tarver [[SelectiveObliviousness manages to keep thinking she's hallucinating]] right up until he starts getting visions too.
* Sylvester in ''Literature/{{Twig}}'' is a TykeBomb who was given massive doses of [[PsychoSerum Wyvern]], a drug designed to allow rapid learning by increasing brain plasticity. The amount Sylvester received allows him to pick up new skills very fast, [[TheSocialExpert analyze people quickly]] and [[IndyPloy make up excellent plans on the fly]]. However, his brain will eventually degrade as the Wyvern breaks down parts of the brain which really need to be in one piece. Around the middle of the book, Sylvester begins seeing hallucinations of his absent friends. Then he starts hallucinating his dead enemies. Then the hallucinations [[SplitPersonalityTakeover start attacking]].
* ''TabletopGame/Warhammer40000'':
** In ''[[Literature/SpaceMarineBattles Fall of Damnos]]'', Sahteh the Enfleshed, a lord of Necron [[HumanResources Flayed Ones]], finds himself less and less self-aware as his craving for a new skin grows stronger. By the end, he can't tell whether he's still alive or already a killer robot, doesn't know what planet he's on and thinks of nothing but getting a new skin.
** In the ''Literature/HorusHeresy'' novel ''Vulkan Lives'', Vulkan is captured by Konrad Curze, who repeatedly tortures [[spoiler:and [[ResurrectiveImmortality kills]]]] him in an effort to break his spirit. These constant torments gradually erode Vulkan’s sanity, causing him to hallucinate that his dead brother Ferrus Manus is mocking him. By the next book in the series, he’s been reduced to a near-feral state where he can’t tell friend from foe and lashes out at everyone around him. [[spoiler:His sanity is ultimately restored in ''Deathfire''.]]
* ''Literature/WarriorCats'':
** [[spoiler:Hollyleaf]], and to a [[BreakTheCutie lesser extent]], her brothers.
** After [[spoiler:her deputy Tigerclaw betrays her]], Bluestar becomes increasingly unstable. She spent most of her time in her nest, frequently had an unfocused, glazed look in her eye, and became snappy. Bluestar began to become paranoid that essentially every cat was out to get her and even thought [=StarClan=] was plotting against her. [[spoiler:She became more like herself [[DyingAsYourself right before losing her]] [[CatsHaveNineLives last life]].]]
* Rand Al'Thor of ''Literature/TheWheelOfTime'' certainly seems to inhabit this trope over the course of at least seven {{Doorstopper}}s. More pressures, more sacrifices and mistakes, more obvious signs of mental instability. After he is [[spoiler:almost captured by legendary psychopathic torturer Semirhage and forced to almost kill Min]] he snaps completely. He adopts DissonantSerenity and engages in more and more questionable deeds. After [[spoiler:almost killing his own father, willingly, out of misplaced rage and paranoia, followed by a bit of fatalist StrawNihilist monologuing on the site of his death in a previous incarnation 3,000 years earlier]] he seems to be showing signs of addressing the slippage though.
* ''Literature/TheWitchlands'': In book two, ''Windwitch'', Merik's sanity takes a beating when he's maddened with grief and in constant pain from the wounds he received at the hands of a would-be assassin. Most notably, he goes from trying to find the evidence needed to apprehend his sister to trying to find an excuse to kill her. Thankfully, he manages to regain his sanity.
* ''Literature/TheWomensRoom'': Lily's descent into madness after her son Carlos is nearly killed by a gang of boys. Although Lily's husband Carl isn't bothered, saying it's just kids being kids, Lily completely snaps, crying and screaming at Carl to kill her, and is committed to a mental institution where she receives electric shock therapy. [[spoiler: If Mira's narration is anything to go by, she's experienced it herself. She even states that she 'wonders if she's going mad.']]
* The narrator of "Literature/TheYellowWallpaper". Understandable, when you're locked in the attic for months, almost totally deprived of outside interaction.
** Of course, a popular theory is that the "attic" in question is actually a room in a mental hospital, and that the narrator is already insane when the story begins.

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