History Main / InsaneEqualsViolent

** "Crazy" Joe Devola, an acquaintance of the gang's who, after learning from Jerry that Kramer didn't invite him to a party, stalks and attempts to murder [[ShootTheMessenger Jerry]], behavior that is eventually attributed to his doctor's failure to refill a prescription.
** Subverted with [[{{Cloudcuckoolander}} the ever-eccentric Kramer]] in the storyline where he travels to LA and is arrested on suspicion of being a serial killer. He is, of course, innocent, but thanks to this trope, even Jerry and George are unsure.

** Subverted with [{{Cloudcuckoolander}} Kramer]] in the storyline where he travels to LA and is arrested on suspicion of being a serial killer. He is, of course, innocent, but thanks to this trope, even Jerry and George are unsure.

** Subverted with [{{[Cloudcuckoolander}} Kramer]] in the storyline where he travels to LA and is arrested on suspicion of being a serial killer. He is, of course, innocent, but thanks to this trope, even Jerry and George are unsure.

* ''Franchise/Tintin'': Zig-Zagged, as a plot point in one of the biggest story arcs (Cigars of the Pharaoh -- Blue Lotus) is the Rajijah juice, a poison that causes madness. Several characters are driven mad by this poison, and the most common symptoms are just that they become a total CloudCuckoolander. Only two characters driven mad by this show any violent tendencies -- Professor Sarcophagus, who was [[MindRape influenced by a Fakir after having already gone mad]], and Didi, who [[AxCrazy encourages people to find the way, and says he'll cut off their head.]] However, he is eventually cured, though not much is known about the other victims of the Rajijah Juice.

* Zig-Zagged in ''Franchise/TheAdventuresOfTintin'', A plot point in one of the biggest story arcs (Cigars of the Pharaoh -- Blue Lotus) is the Rajijah juice, a poison that causes madness. Several characters are driven mad by this poison, and the most common symptoms are just that they become a total CloudCuckoolander. Only two characters driven mad by this show any violent tendencies -- Professor Sarcophagus, who was [[MindRape influenced by a Fakir after having already gone mad]], and Didi, who [[AxCrazy encourages people to find the way, and says he'll cut off their head.]] However, he is eventually cured, though not much is known about the other victims of the Rajijah Juice.
* Franchise/{{Batman}} villains are widely regarded as among the most psychotic and violent in all of comics and thus are serial representatives and offenders of this trope.

** Mr. Freeze is usually one of the few clear aversions in Batman's rogues gallery despite usually being incarcerated at Arkham because the facility can cater to his odd medical needs, as he's not "mad" in the least and is instead just a cruel pragmatist driven by anger, grief, revenge, and hatred. He was turned into a straight example for the New 52 driven by his obsession with Nora who in this reality he's never known and his delusions of a relationship with her (and then soon reverted to his previous version, since the change was highly unpopular).
* Characters/{{Deadpool|WadeWilson}} becomes more unhinged than usual during the Black Box story arc of ''ComicBook/CableAndDeadpool''. Even though he can't remember it later, it is revealed that [[spoiler: he murdered a terrorist who was living on Cable's island]]. When asked why he did it, he replies that he doesn't know. Since his mind is more out-of-whack than usual, he just killed for no reason. However, Deadpool was pointlessly violent long before he was portrayed as insane.
* When Harry Osborn became the second Green Goblin, he was not under influence of the Goblin Serum (though it was later retconned that [[Characters/MarvelComicsNormanOsborn his father]] did give him some), but merely under the influence of drugs and insanity.
* Darryl Cunningham's comic book ''Psychiatric Tales'' is an attempt to demystify mental illnesses and change their perception in media and in society. This trope is played straight in chapter "Antisocial Personality Disorder" (also known as "Mad Or Bad" on Darryl's blog). Other stories are actually an [[InvertedTrope inversion]], stating that people suffering from mental illnesses are more likely to be a victim of crime or harm themselves rather than anyone else.
* In the last arc of ''ComicBook/{{Runaways}}'', Klara suffers a panic attack and lashes out at her teammates, resulting in the destruction of the team's house. To be fair, most of the damage to the house comes not from her personally, but from the plants that she summons (over which her control depends on her emotional state), but she herself punches and kicks Nico Minoru several times, causing the latter to resort to MindRape to force her to calm down.
* In the second volume of ''ComicBook/TheUnstoppableWasp'', A.I.M. attacking G.I.R.L. sets off Nadia's undiagnosed Bipolar Disorder. When the rest of Nadia's friends confront her upon realizing something was wrong with her, they end up aggravating her problems (which were already bad due to sleep deprivation) and she goes violent on them. [[spoiler:When she comes down from that high and realizes what she's done, she's nearly DrivenToSuicide, but is saved by one of her other friends.]]

* Subverted in ''ComicBook/ThirtyDaysOfNight: Bloodsucker Tales'' with Lex Nova, a deranged vampire who believes himself to be a private eye and goes on brutal rampages the second he tastes blood. He's actually a genuinely heroic FriendlyNeighborhoodVampire who only feeds on goats and directs his rampages on other, malevolent vampires and a group of misogynistic {{Serial Killer}}s

** The Yukianesa has had a detrimental effect on Jin Kisaragi's mental health, which manifests in his murderous and psychotic rage that pops up whenever he's near Ragna or Noel, As Jin overcomes the weapon's influence across the series, he also acts noticeably less violent and psychotic and [[SanityHasAdvantages is able to better function in battle]].

** ''Shadow of Israphel'' brings us [[spoiler:Templar_Enoch]]. When he was sane, he wasn't violent, although he was incredibly arrogant. After being driven insane ([[JustifiedTrope due to brainwashing from]] [[spoiler:the Sentinels]], he murders his fellow Templars, realises what he has done, and then [[spoiler:''tears his body apart'']]. Later, LetsPlay/LewisBrindley and LetsPlay/SimonLane meet [[spoiler:the Evil_Honeydew clone duo]], who are both insane and have a love for [[MadBomber TNT]], [[JustifiedTrope due to a malfunctioning cloning machine]].

A fictional character who is insane (in the psychotic, out-of-touch-with-reality way) is usually also violent. Thus, in typical TV-land logic, if you become psychotic, you must also become violent--even if you never were before. A character who already resorts to violence will turn on their friends instead of fighting whatever enemy they usually fight. (Conversely, a villain or antihero who engages in unnecessary violence will often be called "psychotic" as an insult both in- and out-of-universe, even though that character is more often than not completely sane, or at the very least sufficiently sane enough to function normally.)

** In "[[Recap/TheXFilesS07E16Chimera Chimera]]", the monster-of-the-week is revealed to have got some kind of dissociative multiple personality disorder: split personality. The woman's overt self was not aware that it was [[TheKillerInMe her]] who was committing the murders.

* Alpha from ''Series/{{Dollhouse}}'' appears to be this trope -- the composite event that gave him a whole host of imprinted personalities made him into an insane genius and also a psychopathic killer. [[spoiler:Actually an aversion, as his original personality was ''already'' psychopathic before the composite event, and by the time of Epitaph Two has developed a non-insane personality based on all of his component personalities, much like Echo.]]