History Main / APupilOfMineUntilHeTurnedToEvil

** Thus Hohenheim's part in the finale manages to combine the mentor role here with CallingTheOldManOut. Ed gets to be the [[MasterApprenticeChain the third link in the chain]] when they off his big brother.

* Both subverted and inverted ("a pupil of mine until I turned good") in the case of the two female members of the Wrestling/TheInvasion. In the partnership of Wrestling/TorrieWilson and Wrestling/StacyKeibler it was apparently the latter who was the junior partner, with Wilson giving Keibler a demeaning slap on the buttocks to get her moving just before their Bra & Panties Match against Wrestling/{{Lita}} and Wrestling/TrishStratus. But instead of Keibler rebelling against her master, it was Wilson who saw the light, much to Keibler's disgust. By the time the Invasion angle was over, Wilson had established herself as WWE Divas' resident AllAmericanFace - [[HeelFaceRevolvingDoor well, for a time, anyway]] - while Keibler became a successful heel manager and corporate saboteur. In effect, [[VideoGame/KnightsOfTheOldRepublic the Darth Malak to Wilson's Darth Revan]].

* In ''Comicbook/DoctorStrange'' titles, it's [[DependingOnTheWriter not quite clear]] whether the Ancient One's other disciple Baron Mordo was this or a DeceptiveDisciple. [[TheAtoner Maybe a little of both]].

* ''FanFic/ThePiecesLieWhereTheyFell'': Unusually for this trope, it’s the student herself who explains this rather than the teacher -- [[spoiler:Sunset Shimmer reveals she was once Princess Celestia’s personal student, until the Princess felt she wasn’t “worthy” and “forced her out”.]]

* Vargas in ''Videogame/FinalFantasyVI'', [[SelfMadeOrphan kills his father]] and master out of the belief that he favored Sabin.

[[folder:Web Comics]]

* ''WesternAnimation/JoeOrioloFelixTheCat'': the Master Cylinder was an academy student of the Professor's when a lab explosion caused him to be housed in a tin casing. He proclaims himself to be king of the moon and is not beneath double-crossing the Professor.

->''"A young Jedi named Darth Vader, who was a pupil of mine until he turned to evil, helped the Empire hunt down and destroy the Jedi Knights. He betrayed and murdered your father."''

In ''VideoGame/TheLegendOfZeldaSpiritTracks'', Bryne was an apprentice of Anjean in the Tower of Spirits. He desired power from the good spirits, and when he was not granted it, he left and reached out to serve the King of all Evil, Malladus.

* In ''Franchise/StarWars'', Anakin Skywalker, who stuidied under Obi-Wan Kenobi, was a good man, if arrogant and quick to anger, until he was seduced by the dark side (specifically, by Palpatine, who promised him a way to save his wife from her imminent death). He wound up becoming the Sith lord Darth Vader and right-hand to Palpatine, and an enemy of the very man who trained him. Much of Luke's arc is him worrying if [[TurnOutLikeHisFather he will go down the same path]].

->''"A young Jedi named Darth Vader, who was [[TropeNamer a pupil of mine until he turned to evil]], helped the Empire hunt down and destroy the Jedi Knights. He betrayed and murdered your father."''

->''"A young Jedi named Darth Vader, who was a pupil of mine until he turned to evil, helped the Empire hunt down and destroy the Jedi Knights. He betrayed and murdered your father."''

* ''Fanfic/ChildOfTheStorm'' has this tend to be a sign that Doctor Strange is not quite as infallible as he appears and lets everyone believe. In the sequel, he rather sadly states that he's only taken five students (four at the start of the story, the fifth being [[spoiler: Harry]]) over his extremely long life, and only one -- Wanda Maximoff - turned out well [[SoProudOfYou (indeed, he says that he could not be more proud of her, and her success was more down to her virtues as a student than his as a teacher)]].

Not to be confused with EvilEye or HellishPupils. This is "pupil" as in a student, not part of an eye.

** The first anime played with the trope in that ''Ed's'' master Izumi Curtis [[MasterApprenticeChain had trained with]] an old woman named Dante, who turned out to be the villain.

* In ''Franchise/StarWars'', Anakin was a good man, if arrogant and quick to anger, until he was seduced by the dark side. Much of Luke's arc is if he will go the same path.

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* In ''Manga/SoulEater'', Asura was Shinigami's apprentice [[spoiler:and as it turns out, son]] until he went insane and threatened to destroy the world, and had to be sealed away.

* ''Manga/FullMetalAlchemist'' pulls a variation, in that Homunculus kind of mentored Slave #23 from the day he gave him his name...but recognized Van Hohenheim as "his father." Given his entire identity is later molded around the fatherly role, this concept is clearly significant to him.
** Thus Hohenheim's part in the finale manages to combine the mentor role here with CallingTheOldManOut. Ed gets to be the [[MasterApprenticeChain the third link in the chain]] when they off his big brother.
** The first anime played with the trope in that ''Ed's'' master Izumi Curtis [[MasterApprenticeChain had trained with]] an old woman named Dante, who turned out to be the villain.
* ''Franchise/DragonBall'':
** In ''Manga/DragonBall'', the Master Roshi states that Master Shen used to be a fellow student of the mighty Mutaito, who underwent a FaceHeelTurn after seeing the might of [[BigBad Demon King Piccolo]], having apparently decided that BeingGoodSucks.
** In ''Anime/DragonBallSuper'', Zamasu is Gowasu's student, chosen to become the next Supreme Kai of Universe 10. However, Zamasu's [[BlackAndWhiteInsanity black and white views on mortals]] cause him to see the beings he's suppose to guide and protect as being unworthy of the gods' knowledge. Meeting Goku and going to Planet Babari only solidified his bias, and concludes that ''all'' mortals need to be wipe out for universal peace. [[spoiler: To that end, Present Zamasu tries to murder Gowasu and steal his Time Ring]]. When Gowasu was told of this, he is ''definitely'' not pleased. [[spoiler: The Zamasu who would become Black not only killed his master for the earrings, but also killed Future Gowasu]].
*** The same can be said for [[spoiler:Goku Black, since he is actually an alternate Present Zamasu who succeeded in murdering his master Gowasu.]]

* In episode 10 of ''Anime/SamuraiChamploo'', the gang meets up with a friendly monk who turns out to have been a former martial arts teacher who once taught Shoryuu, the villain of the episode. He had encouraged Shoryuu to travel and hone his skills, but this went horribly wrong, when after learning an amazing technique, Shoryuu became obsessed with proving his greatness by challenging and killing any martial artist he could find.
* ''Manga/RurouniKenshin'': The trope title is almost a word-for-word utterance by [[{{Ninja}} Old Man Okina]] after fully realizing that his most beloved disciple, Aoshi, has fallen entirely to the dark side-- and is in league with [[BigBad Makoto Shishio]], to boot. Specifically, he ask Kenshin to put an end to Aoshi's life. However, in a moment that also defies BrokenPedestal on Misao's part, Kenshin refuses to do it, he believes that Aoshi still possess a trace of goodness in his heart. A few hard knocks later, [[DefiedTrope Aoshi realizes the errors of his way.]]

* ''Literature/DemonCityShinjuku''. Levih Rah was once the student and ally of his master Agni Lai, who taught him the art of Nempo. Unfortunately he was envious of the power of other men and ended up selling his soul to the demons of Hell in return for vast power.

* In ''Comicbook/DoctorStrange'' titles, it's [[DependingOnTheWriter not quite clear]] whether the Ancient One's other disciple Baron Mordo was this or a DeceptiveDisciple. [[TheAtoner Maybe a little of both]].
* ''ComicBook/LaQueteDeLOiseauDuTemps'' has Bulrog; a former student of the knight Bragon who turned mercenary and eventually ends up seeking vengeance on his master.

* Inverted in ''ComicBook/DeathVigil'' by [[spoiler: Wulf, who was Sam's mentor in the Vigil. Wulf was a loyal and respected member of the Vigil for centuries, but then his gifted surrogate daughter was killed in an accident and Bernie was unable to do anything for her. Although we never hear her reasoning from ''Bernie's'' perspective, Wulf claims she refused him, and [[FaceHeelTurn didn't take it well]]]].

* In ''ComicBook/MoonKnight'', Jeff Wilde, the son of villain the Midnight Man, takes on the superheroic persona of Midnight and attaches himself as sidekick to the reluctant Marc Spector. The HYDRA breakaway sect Secret Empire capture him and subject him to UnwillingRoboticisation, causing him to turn AxCrazy.

* ''Fanfic/ChildOfTheStorm'' has this tend to be a sign that Doctor Strange is not quite as infallible as he appears and lets everyone believe. In the sequel, he rather sadly states that he's only taken five students (four at the start of the story, the fifth being [[spoiler: Harry]]) over his extremely long life, and only one - Wanda Maximoff - turned out well [[SoProudOfYou (indeed, he says that he could not be more proud of her, and her success was more down to her virtues as a student than his as a teacher)]].
** Mordo was this, though it's ambiguous, because his main impact (he hasn't appeared) is in his own choice of student - Victor von Doom. The sheer [[TheChessmaster scale]] of [[ManipulativeBastard manipulation]] [[GoodIsNotNice and ruthlessness]] this version of Strange is capable of means it's possible that he actually intended for Mordo to fall (assuming that Mordo wasn't a DeceptiveDisciple to begin with), in order to teach Doom in turn.
** An unambiguous case is one of Strange's other students, revealed in the sequel to be [[spoiler: Margaret Le Fay, mother of [[Literature/TheDresdenFiles Harry Dresden]]]]. He took her in when she was seeking other viewpoints to the White Council's rigid stance of non-interference/focus on [[TheFettered fettering magical power]] rather than using it to make a difference, teaching her how to handle BlackMagic safely (figuring that she was going to experiment anyway), but she left after deciding that he was too cautious and more concerned with the future rather than the present, joining up with darker forces. While Strange had anticipated this, he was hoping she would only skim the surface without pulling a true FaceHeelTurn - and while she did pull a HeelFaceTurn in the end, [[spoiler: it got her killed]].
* ''FanFic/ThePiecesLieWhereTheyFell'': Unusually for this trope, it’s the student herself who explains this rather than the teacher - [[spoiler:Sunset Shimmer reveals she was once Princess Celestia’s personal student, until the Princess felt she wasn’t “worthy” and “forced her out”.]]

** In ''WesternAnimation/KungFuPanda2'', this can be said of Lord Shen and the Soothsayer, who raised him. In this case, Shen never actually ''attacks'' the Soothsayer (in fact, she's the only one who can get away with insulting him - repeatedly - without being killed), but that doesn't mean he'll listen to any of her pleas to stop his mad dreams of conquest.

* This is [[DiscussedTrope discussed]] in ''Literature/TheInheritanceCycle''. Neither of Eragon's teachers, Brom or Oromis, taught the BigBad of the series, Galbatorix (Brom would have been too young being a decade and a half younger than Galbatorix). Oromis says he's glad for it because Galbatorix made sure to personally kill anyone that was involved in his teaching. However, Oromis ''did'' train Galbatorix's late [[TheDragon right-hand man]] Morzan.
* A number of Luke Skywalker's Jedi students in Franchise/StarWarsLegends end up eventually falling to the Dark Side. He's able to bring some of them back.
** Kyp Durron, a young man in the ''Literature/JediAcademyTrilogy'' purportedly even stronger in the Force than the Skywalkers, is seduced to the dark side by the ghost of the ancient Sith Lord Exar Kun and takes a leftover Imperial superweapon on a bloody rampage against the Imperial Remnant before the other apprentices destroy Exar Kun and Han and Lando are able to talk Kyp down. In later books he becomes TheAtoner.
** Brakiss intended to be a DeceptiveDisciple, but Luke believed he could be turned; Brakiss started BecomingTheMask until Luke put him through a test which horrified him and caused him to flee. Luke always believed that Brakiss could be redeemed, and in ''Literature/TheNewRebellion'' parts written from Brakiss's point of view suggest that he'd like that, but [[DoomedByCanon it's not to be]]: [[spoiler:Brakiss is on the receiving end of a HeelFaceDoorSlam courtesy of a surviving Imperial Royal Guard at the end of the Shadow Academy arc in ''Literature/YoungJediKnights'']].
** Dolph Kueller in ''Literature/TheNewRebellion'' is never really clearly explained [[spoiler:and dies at the end of his only appearance]].
** Alema Rar, debuting in ''The Literature/NewJediOrder: Star By Star'', suffers a CynicismCatalyst in the form of witnessing her identical twin sister being killed by a Yuuzhan Vong creature bred to hunt and kill Jedi, and becomes an advocate of purportedly un-Jedi-like tactics against the Vong (e.g. using leftover Imperial superweapons). In ''The Literature/DarkNestTrilogy'' Luke ultimately expels her from the Order over her behavior, [[spoiler:and she spends the trilogy as the GoldfishPoopGang before being unceremoniously EatenAlive by a critter]]. Except it turns out that she survived this, and spends most of ''Literature/LegacyOfTheForce'' half-insane and determined to take down Han and Leia.

* The Darklord Lorthas, former student of High Wizard Aemon in ''Literature/BoundarysFall''. [[AntiVillain He's still not entirely bad.]]

* PlayedForLaughs in ''Literature/RulerOfTheMagicalKeys'', where the pupil in question is a cat who learned only one spell – the one that could turn anyone and anything into a mouse – and just went on searching for a good supper and [[KnightTemplar getting rid of evil dogs]].

* Inverted with Master Eubulon in ''Series/KamenRiderDragonKnight''.

* In ''TabletopGame/HeroQuest'', BigBad [[DubNameChange Morcar/Zargon]] was a student of [[HisNameReallyIsBarkeep Mentor]] who got fed up with not being taught magic fast enough, read texts forbidden to him in secret, gained great power, and ran off to become the [[EvilOverlord Lord of Chaos]].

* Vargas in ''Videogame/FinalFantasyVI'', [[SelfMadeOrphan kills his father]] and master out of the belief that he favored Sabin.
* In ''VideoGame/FinalFantasyXIV'', the Samurai job questline entails helping the wandering warrior Musosai pursue a criminal named Kogarashi, whose crimes include mentoring a pupil who used his teachings to commit murder. Under Hingan law, a samurai must take responsibility for any and all crimes committed by their pupils. [[spoiler:Eventually, Musosai reveals that he is Kogarashi before his final fight with the player. His pupil plays a bigger role in subsequent job quests.]]

* ''VideoGame/LegendOfLegaia''
** Songi is this to Master Zopu and a RivalTurnedEvil to Gala. Zopu and Maya both state that Songi was a good child, but his pride and anger at always being second best to Gala caused his decent unto evil.
** Kazan's former pupil was the swordsman [[spoiler:Rauss.]] The latter was gradually corrupted by the [[DangerousForbiddenTechnique Ultimate Fang]] into a BloodKnight, and his desire to fight his former master led him to a FaceHeelTurn ending with the master killing his former pupil.
* The Naughty Sorceress of ''VideoGame/KingdomOfLoathing'' can be found in Fernswarthy's ethics class. He wasn't that nice a guy, but she wasn't that good a student either.

* ''Franchise/KingdomHearts'': The first six members of Organisation XIII were pupils to Ansem [[spoiler: the Wise, the king of Radiant Gardens]] who helped him in his research into the Heart. Eventually, they turned on him and turned themselves into Heartless. [[spoiler: Only not really. Only Xehanort and Braig apply. The other Apprentices were forcibly turned into Heartless and were manipulated into joining Xemnas under false pretenses upon becoming Nobodies.]]
* In ''VideoGame/AtlasReactor'', OldMaster Su-Ren views [[{{Ninja}} Kaigin]], who was formerly her student, this way. Given the {{Cyberpunk}} GreyAndGrayMorality of the setting the truth is a little more complicated than that, but it's very clear that the two of them are not on the same side. In a slight deviance from the trope, Su-Ren never considered Kaigin her best student but [[TheUnfavourite rather the opposite]].
* ''VideoGame/ForeverHome'': Corporal Slash once took in two street urchins, Barclyss and Heindrovia, to recruit them into the [[LaResistance Aurian resistance]] and to teach them how to harness their innate magical talents. Both started out kind and generous, but Barclyss eventually became a psychopath willing to kill the resistance's [=POWs=], causing him to be expelled. While Heindrovia still retained most of her good qualities, she ended up following Barclyss out of misguided love.
* The ''Franchise/MortalKombat'' series has Frost, a Lin Kuei assassin and cryomancer that Sub-Zero took under his wing, until she decided to try and kill him so she can take control of the Lin Kuei for herself. In ''VideoGame/MortalKombat11'', she turns to evil and joins Sektor and Kronika, voluntarily turning herself into a Cyber Lin Kuei and leading the Tekunin, overseeing the horrific process of [[UnwillingRoboticization turning Lin Kuei into cyborgs]]. When he sees her again, Sub-Zero is visibly disgusted at what his once-protegee has become.
* ''VideoGame/GhostOfTsushima'' has Tomoe, a talented peasant woman who was trained in the Way of the Bow by master archer Sensei Ishikawa, who treated her as though she were his own daughter. Unfortunately, Ishikawa pushed Tomoe too hard due to his perfectionist methods, resulting in her snapping and attacking him before fleeing. When she gets captured by the Mongols, Tomoe offers her services to them and teaches them Ishikawa's Way of the Bow, which they use to terrorize the people of Tsushima, and it's up to Jin Sakai to help Ishikawa stop Tomoe throughout the latter's questline.

* In ''Webcomic/OurLittleAdventure'', Thomas Stratus was one of [[BigBad Brian Souballo's]] old magic teachers back before Brian went all megalomaniacal.

* Fukushima from the ''WesternAnimation/KimPossible'' episode "Exchange" was a student of the Yamanuchi Ninja School. He turned out to betray the school and helped Monkey Fist obtain a powerful weapon. It's not really explored why he did so, either he was already paid by Monkey Fist, or he only turned after Ron came to Japan. He could have felt insulted that Ron received honors that according to him should not be given to "outsiders". Or else he became [[LoveMakesYouEvil jealous of Yori's shows of affection]] for Ron.

* ''WesternAnimation/TransformersAnimated''. While never really elaborated on, [[BountyHunter Lockdown]] was once a pupil of [[OldMaster Yoketron's]]. At some point, he abandoned the Cyber-Ninja dojo - only to return, sometime after Prowl joined, to make off with the dojo's protoforms and to kill Yoketron. Oilslick may also apply for this trope, but with the lack on information on his past, it's debatable.

* Zhao from ''WesternAnimation/AvatarTheLastAirbender'' is a former pupil of Jeong-Jeong’s. Once he learned how to Firebend, he then sought to use his abilities to aid his own ambitions. Jeong-Jeong tells Aang that his pupil (who he didn’t name at the time) never learned self-control and his bending becoming more dangerous and untamed.

* Played with in ''WesternAnimation/BatmanBeyond'' with Kairi Tanaga and her pupil Zander. Zander was a test-tube baby created by [[NebulousEvilOrganization Kobra]] to be the perfect leader and had thus been effectively brainwashed from birth to follow their teachings and beliefs, while Kairi believed deep down he was not an evil person at heart but simply doing what he'd been taught to do from day one, and that [[HeelFaceTurn she could save him]] by teaching him the honorable ways of the Bushido. [[spoiler:While he certainly has virtues and is mostly ObliviouslyEvil, he never-the-less [[HeelFaceDoorSlam can't be swayed]] and dives head-first into the role of the evil leader of Kobra, resulting in [[DownerEnding he and Kairi's deaths]]]].
* ''WesternAnimation/JoeOrioloFelixTheCat'': the Master Cylinder was an academy student of the Professor's when a lab explosion caused him to be housed in a tin casing. He proclaims himself to be king of the moon and is not beneath double-crossing the Professor.

* In ''WesternAnimation/DungeonsAndDragons'', the Dungeon Master revealed that Venger was a former pupil. In the unaired series finale Venger is revealed to be Dungeon Master's son.

Compare DeceptiveDisciple (when the student was [[EvilAllAlong evil the whole time, just pretending not to be]]), FallenHero, MerlinAndNimue, UsedToBeASweetKid, and TheParagonAlwaysRebels.

* This is [[DiscussedTrope discussed]] in ''Literature/TheInheritanceCycle''. Neither of Eragon's teachers, Brom or Oromis, taught the BigBad of the series, Galbatorix. Oromis says he's glad for it because Galbatorix made sure to personally kill anyone that was involved in his teaching.

* Subverted in ''ComicBook/BatmanLastKnightOnEarth'', as over the course of the story, the characters speculate that Omega was a protege of Batman who went rogue and betrayed his ideals, [[spoiler:but while technically the latter is true, Omega didn't betray Bruce -- as it turns out that Omega is actually [[FallenHero Bruce Wayne himself]].]]

* Subverted in ''ComicBook/BatmanLastKnightOnEarth'', as over the course of the story, the characters speculate that Omega was a protege of Batman who went rogue, [[spoiler:but Omega turns out to be [[FallenHero Bruce Wayne himself]], so while technically, yes, Omega betrays Bruce's former ideals, he didn't actually betray Bruce on account of him actually being Bruce.]]

* Subverted in ''ComicBook/BatmanLastKnightOnEarth''. It's speculated by the characters that Omega was a protege of Batman who went rogue, [[spoiler:but Omega turns out to be [[FallenHero Bruce Wayne himself]]]].

* ''VideoGame/{{Ghost of Tsushima}}'' has Tomoe, a talented peasant woman who was trained in the Way of the Bow by master archer Sensei Ishikawa, who treated her as though she were his own daughter. Unfortunately, Ishikawa pushed Tomoe too hard due to his perfectionist methods, resulting in her snapping and attacking him before fleeing. When she gets captured by the Mongols, Tomoe offers her services to them and teaches them Ishikawa's Way of the Bow, which they use to terrorize the people of Tsushima, and it's up to Jin Sakai to help Ishikawa stop Tomoe throughout the latter's questline.