History Main / BigBadSlippage

[[AC: {{Anime}} and {{Manga}}]]

[[AC:ComicBooks]]

[[AC:{{Film}}-Animated]]

[[AC:{{Film}}-Live Action]]

[[AC:{{Literature}}]]
* In ''Literature/{{Gormenghast}}'', Steerpike begins as a rebel dissatisfied with the lowly position allocated to him at birth. He runs out on his assigned job as a kitchen scullion and sets about - metaphorically and literally - climbing to a higher social station, despite the law and tradition of the city-state. In the beginning, the reader can sympathise with him for his ambition, for wanting to break with stultifying convention, for wanting to get a satisfying position in line with his intelligence and talent. An occasional lie and a bit of confidence trickery can be forgiven. But then people start to die. The sympathetic young rebel is becoming a monster. He finally dies as a scarred and deformed monster, having murdered the heroine Fuchsia and hunted down by her brother.

[[AC:LiveActionTv]]

[[AC:{{Mythology}}]]

[[AC:VideoGames]]

[[AC: WesternAnimation]]

** Though, as of Issue 50, a case could be made for Optimus Prime doing the same.

Subtrope of FaceHeelTurn. Can also coincide with SlowlySlippingIntoEvil. When a rebel leader undergoes this, it's also a case of TheParagonAlwaysRebels. Can coincide with ThenLetMeBeEvil, when a character who has been treated as evil, regardless of their actions, says "screw it" and decides to meet everyone's expectations by being evil. Compare StartOfDarkness, which shows how the character became evil via a {{prequel}} story or {{flashback}}s. Compare ProtagonistJourneyToVillain, when the main protagonist crosses over to the dark side (but not necessarily become a BigBad) over the course of the story. Contrast EvilAllAlong, where the character is always evil rather than just slipping into evil.

* ''ComicBook/TheFlash'' has Hunter Zolomon, the second Reverse-Flash/Zoom who was initially introduced as a simple supporting character in the Keystone police department far into then Flash Wally West's superhero career and developed throughout years in friendship role, until his shocking FaceHeelTurn. And even that said heel turn happens almost [[SlowlySlippingIntoEvil a year after]] when his StartOfDarkness begins upon being paralyzed by Grodd.

* ''VideoGame/WarcraftIII'''s human campaign has Prince Arthas Menethil gradually taking more and more desperate and {{antihero}}ic measures in his efforts to save Lordaeron from [[TheUndead the Scourge]]. This ultimately results in him taking up the cursed blade Frostmourne in Northrend and becoming a death knight in service to the Scourge himself.

** The Conquest route, though he isn't the BigBad, also has Takumi, your younger brother on the Hoshido side. He's easily the most RecurringBoss of the Hoshido siblings, fought as many as [[spoiler:five]] times compared to elder siblings Ryoma and Hinoka, tied with three if you count the battle at the start of the route split. Each time, he only gets more and more violently enraged with you and the other [[FantasticRacism Nohrian Scum]]'s general existence and "betrayal," acting more antagonistic overall than anyone else in Hoshido,[[spoiler:even returning from his presumed suicide and acting as the FinalBoss of the route even after you've defeated [[DiscOneFinalBoss King Garon and his cronies]]]]. [[spoiler:Similarly to King Garon, but not quite identically, this was partially the result of the influence of the GreaterScopeVillain, though he was only able to do this so extensively due to Takumi's own anger being unchecked.]]

* The Black Wizard Zeref from ''Manga/FairyTail'' is built up over the whole story as being an evil GreaterScopeVillain who will become the BigBad when resurrected/unsealed. When it turns out that he was not only alive and not sealed, but a man who hates his own crimes, his BigBad status seems to be subverted. However, his very presence makes him an antagonist anyway, and as things die around him because of his magic and as he sees how HumansAreBastards, he begins deliberately using his powers to kill anyone he sees as evil. Eventually decides to become the [[ThenLetMeBeEvil evil man that everyone thought he was]] and becomes a full on antagonist for the rest of the series.

** Harry Osborn starts off as a friend to Peter Parker. However, Harry's stress over his disease that will kill him causes him to lose his sanity over the course of the movie and become more antagonistic to Peter. This comes to a head when he teams up with Electro and is injects with a serum that turns him into the Green Goblin.
** Max Dillon is initially a timid worker at Oscorp who's TheChewToy until he gets into an accident of falling into a pool full of electric eels while at work (he's the engineer). After that he becomes Electro, and he's not a baddie yet... then he goes to the Times Square at night where people are scared of him... but he's happy that people start recognizing him. Up until a wayward sniper shoots him, making his electric powers go out of control and Spider-Man trying to suppress him; people start cheering for Spidey, and this makes Electro deems him his enemy. From then on he becomes one of the villains.
* ''Film/{{Maleficent}}'' has King Stefan, who while kicking off the story by stealing Maleficent's wings and sending Aurora away, is not exactly evil at those points. By the end of the story however, paranoia has broken him and he tries to kill Maleficent [[spoiler:even though she just saved his daughter]].
* Loki from ''{{Film/Thor}}'' is the title character's apparent brother and starts off as mostly good but jealous. It is revealed to be a Frost Giant part way through the film and that he let the Frost Giants into Asgard earlier in the film so he could stop them himself out of jealousy over Thor. When the reveal that he's a Frost Giant comes, he decides to take over Asgard. He manipulates King Laufey into helping him, pretending they're a BigBadDuumvirate, and betrays him at the end of the film, leaving Loki as the sole BigBad.

* In ''Literature/ShadowsOfTheApt'', Seda is introduced as the timid princess of [[TheEmpire the Wasps]] who lives in constant fear that her older brother [[TheCaligula Emperor Alvdan]] will someday have her assassinated like he did their other siblings. This starts to change when Alvdan's advisor [[EvilSorcerer Uctebri]] takes Seda under his wing, at which point she gains knowledge of BloodMagic and a significant injection of confidence. At this stage she starts demonstrating her true [[TheChessmaster competence]] and [[AmbitionIsEvil ambition]], and ultimately outlasts both Alvdan ''and'' Uctebri. Seda ends up becoming [[TheArchmage an immensely powerful magician]] as well as Empress, and holding the throne of BigBad for most of the second half of the series.

* Slade Wilson in ''Series/{{Arrow}}'' starts off being stuck on the island with Oliver. He helps train Oliver to make him into a skilled fighter. After being badly burned Oliver, Shado and Sara using the drug Mirakuru to save him. It works but there are nasty side-effects that cause Slade to be mentally unstable. Soon after giving him the drug Oliver, Shado and Sara are captured and Oliver is forced to choose to save one of them, [[spoiler:he chose Sara.]] When Slade finds out he is dead set on destroying Oliver in every way possible.
* [[spoiler:Jiaying]] from ''Series/AgentsOfSHIELD'' is in charge of Afterlife and the head figure of the Inhumans there. While she is rather nice at first (especially to [[spoiler:her daughter, Skye]]), her nasty side begins creating a lot of conflict concerning the Inhumans, to the point where [[spoiler:Jiaying kills Agent Gonzales and starts a war between the Inhumans and S.H.I.E.L.D.]]. [[spoiler:And in a subversion, she's actually behind the actions of Cal, making her the BigBad the whole time.]] It turns out that she actually was a nice person to begin with, but was [[spoiler:vivisected by Dr Whitehall and CameBackWrong thanks to Cal's efforts to save her]].
* On ''Series/{{Grimm}}'', Adalind removes Nick's powers through a magic ritual. Juliette agrees to restore them through another ritual, but it has the side effect of turning her into a Hexenbiest. Then she starts to have a complete morality breakdown leading to her starting fights in bars using her new powers, setting fire to the trailer where Nick keeps his journals, and conspiring with the villains to kidnap Adalind's daughter. That last act also leads to [[spoiler: the death of Nick's mother.]]
** [[spoiler: And leads to her being KilledOffForReal...apparently.]]

** The sequel ''VideoGame/WorldOfWarcraft'' continues the trend with Garrosh Hellscream, who is introduced in ''Burning Crusade'' as a minor character and gets brought back in ''Wrath of the Lich King'' as an alley, if a somewhat jerky one. Then he replaces [[ReasonableAuthorityFigure Thrall]] as the Horde's Warchief. Cue him growing progressively more [[TyrantTakesTheHelm tyranical]], [[JerkAss unlikable]], [[FantasticRacism racist]] and [[GeneralRipper pointlessly hostile toward the Alliance]], eventually leading to the other Horde leaders all rebelling against him and [[EnemyMine teaming up with the Alliance]] to take him down.

* Eddie Brock in ''WesternAnimation/TheSpectacularSpiderMan'' starts out as Peter Parker's long-time best friend and a genuinely nice guy, only for a chain of event to lead him to become gradually more bitter toward both Spider-Man and Peter, culminating in his transformation into ComicBook/{{Venom}}.

* ''BeyondTwoSouls'': [[spoiler:Nathan]]. We get to witness signs of his gradual slippage during the course of the story, even though the most notable stages of it are revealed in the last stages (partly due to the game's disjointed narrative).

* Similarly, ''VideoGame/StarCraft'''s Terran campaign has Arcturus Mengsk start out as a RebelLeader and the closest thing the campaign has to a BigGood, only to gradually use more questionable methods to overthrow the corrupt Confederacy, culminating in him unleashing a [[HordeOfAlienLocusts Zerg]] [[AlienInvasion invasion]] [[MoralEventHorizon on their home planet and leaving his most faithful lieutnant to die with them]]. Cue [[TheHero Raynor]] quitting out of disgust and Mengsk proclaiming himself TheEmperor, setting him up as the main human villain of the franchise.

* ''VideoGame/WarcraftIII'''s human campaign has Prince Arthas Menethil gradually taking more and more desperate and {{antihero}}ic measures in his efforts to save Lordaeron from the Undead Scourge. This ultimately results in him taking up the cursed blade Frostmourne in Northrend and becoming a death knight in service to the Scourge himself.

* ''WesternAnimation/{{Megamind}}'' starts off as a VillainProtagonist BigBad. When he gets bored after seemingly (but not really) killing his arch-nemisis Metro Man and taking over Metro City, he decides he needs a new nemesis and creates one out Hal Stewert, attempting to shape him into a superhero known as Titan. However, WrongGenreSavvy Hal believes that getting superpowers will automatically cause Roxanne to fall in love with him, but when she still rejects him, he decides to be a super villain instead. This is what leads to Megaminds HeelFaceTurn part way through the movie.

* [[spoiler:Jiaying]] from ''Series/AgentsOfSHIELD'' is in charge of Afterlife and the head figure of the Inhumans there. While she is rather nice at first (especially to [[spoiler:her daughter, Skye]]), her nasty side begins creating a lot of conflict concerning the Inhumans, to the point where [[spoiler:Jiaying kills Agent Gonzales and starts a war between the Inhumans and S.H.I.E.L.D.]]. [[spoiler:And in a subversion, she's actually behind the actions of Cal, making her the BigBad the whole time.]]

* ''There's a Man in the Woods'': This short animated film tells a story of a man who gets fired from a teaching job because one of his pupils lies about seeing a serial killer near the playground, and then gradually turns more and more stressed-out and mentally unstable until he becomes a serial killer himself.

* ''Film/TheAmazingSpiderman2'' has both members of the BigBadDuumvirate go through this.

* The UrExample is Loki from NorseMythology, a half-Aesir/half-Jotunn who starts off as a trickster friendly to the Aesir but eventually becomes their worst enemy; he and his sons end up killing the greatest of the Aesir.

* Kenny from Season Two of ''VideoGame/TheWalkingDead'' was your ''ally'' mere episodes earlier - but Kenny's temper and SanitySlippage slowly turned him into a BigBad.

Subtrope of FaceHeelTurn. Can also concede with SlowlySlippingIntoEvil. When a rebel leader undergoes this, it's also a case of TheParagonAlwaysRebels. Can coincide with ThenLetMeBeEvil, when a character who has been treated as evil, regardless of their actions, says "screw it" and decides to meet everyone's expectations by being evil. Compare StartOfDarkness, which shows how the character became evil via a {{prequel}} story or {{flashback}}s. Compare ProtagonistJourneyToVillain, when the main protagonist crosses over to the dark side (but not necessarily become a BigBad) over the course of the story. Contrast EvilAllAlong, where the character is always evil rather than just slipping into evil.

* The Black Wizard Zeref from ''Manga/FairyTail'' is built up over the whole story as being an evil BiggerBad who will become the BigBad when resurrected/unsealed. When it turns out that he was not only alive and not sealed, but a man who hates his own crimes, his BigBad status seems to be subverted. However, his very presence makes him an antagonist anyway, and as things die around him because of his magic and as he sees how HumansAreBastards, he begins deliberately using his powers to kill anyone he sees as evil. Eventually decides to become the [[ThenLetMeBeEvil evil man that everyone thought he was]] and becomes a full on antagonist for the rest of the series.

* In ''Literature/{{Ghormenghast}}'', Steerpike begins as a rebel dissatisfied with the lowly position allocated to him at birth. He runs out on his assigned job as a kitchen scullion and sets about - metaphorically and literally - climbing to a higher social station, despite the law and tradition of the city-state. In the beginning, the reader can sympathise with him for his ambition, for wanting to break with stultifying convention, for wanting to get a satisfying position in line with his intelligence and talent. An occasional lie and a bit of confidence trickery can be forgiven. But then people start to die. The sympathetic young rebel is becoming a monster. He finally dies as a scarred and deformed monster, having murdered the heroine Fuchsia and hunted down by her brother.

* [[spoiler:Jiaying]] from ''Series/AgentsOfSHIELD'' is in charge of Afterlife and the head figure of the Inhumans there. While she is rather nice at first (especially to [[spoiler:her daughter, Skye]]), her nasty side begins creating a lot of conflict concerning the Inhumans, to the point where [[spoiler:Jiaying kills Agent Gonzales and starts a war between the Inhumans and S.H.I.E.L.D.]].

* In the final season of ''WesterAnimation/TheLegendOfKorra'', Kuvira starts out as a harmless background character who helps save Korra's father in the season 3 finale. However, she is later put in charge of stabilizing the Earth Kingdom after the assassination of the queen, and her fascist methods of unifying the country put her at odds with the main characters.