Harry Morgan: Son, there are people out there who do really bad things. Terrible people. And the police can't catch them all. Do you understand what I'm saying?
Dexter Morgan: You're saying...they deserve it.A violent, psychotic killer with a Freudian Excuse gets sick pleasure out of the suffering of his victims. It sounds like he's your basic Serial Killer, right? He would be, but instead of terrorizing the innocent, the Serial-Killer Killer terrorizes the guilty. He spends his life tracking down serial killers so he can give them justice. In short, he's a vigilante, who thinks himself divine justice incarnate. For this reason, he kills them in the same way they'd kill their own victims. Distinct from He Who Fights Monsters because He Who Fights Monsters is more about good characters turning evil in the process of hunting evil, whereas this is more about someone who is evil, or crazy, or both from the outset. Arguably, this guy can be Chaotic Good and be an Anti-Hero, although he walks a VERY dangerous line to become the Knight Templar. See also Smiting Evil Feels Good, Vigilante Man, Knight Templar, Pay Evil unto Evil, Hunter of His Own Kind, The Killer Becomes the Killed, '90s Anti-Hero, Bully Hunter, Defends Against Their Own Kind, and Asshole Victim. Compare with the similarly named Wife-Basher Basher, which they often are too. Contrasts Bounty Hunter and Professional Killer, while they may also hunt serial killers, they are Only in It for the Money.
As a Death Trope, all Spoilers will be unmarked ahead. Beware.
open/close all folders
Anime and Manga
- Rio from Ana Satsujin mainly kills criminals, though she hates police and makes an exception for them. She will technically kill anyone she feels like, which includes her boyfriend.
- Vino from Baccano! counts. An incredibly violent assassin, he generally prefers to kill by smashing his targets' faces into the ground from a moving train. However, he takes pride in only killing other criminals, and refuses to do jobs on people who are not guilty. In its main plot aboard the Flying Pussyfoot, Vino actually can be considered the most heroic of those involved, as his brutal murder spree only involves the cultists and gangsters who were trying to harm the passengers. He even saves the comic relief from certain death.
- Code:Breaker. Some of the Code Breakers recognize that they are evil themselves, though.* Both Sparkling Justice and Killer Killer from Dangan Ronpa exclusively kill criminals.
- Almost all incarnations of Kira in Death Note fall under this trope, with the exception of the one profit-driven Corrupt Corporate Executive. Most notably, the main character Light is a mix of Knight Templar and A God Am I, believing he'll become the "god of the new world" by completely eradicating the world's criminals. True to the series' penchant of showing what happens to He Who Fights Monsters, a good number of the Kiras Jump Off the Slippery Slope into Knight Templar (such as Light himself) or just plain Ax-Crazy (such as Mikami) territory.
- Haseo from DOT Hack, nicknamed "Terror of Death" due to his insistence on killing PKers (which makes him a PKer-Ker).
- Diana, Selacao number 11 in Eden of the East, hunts rapists and dispatches them by castration via cigar cutter.
- Scar of Fullmetal Alchemist is pretty much this, except replace "serial killer" with "war criminal." Indeed, he assassinates his targets using the same power that they use to commit their war crimes.
- Kuroko, the protagonist of Murciélago has murdered 725 people, and the only reason she hasn't been given the death sentence is so she can kill other mass-murderers.
- Marvel Universe
- The Punisher hunts and kills as many criminals as he can. Currently he's killed over 48,000.
- Venom from Spider-Man (Depending on the Writer).
- Night Raven, from Marvel UK (though his stories take place mostly in the US), has targeted serial murderers, including an unauthorized successor to his mantle, Howard Bates, who had admired Night Raven as a child.
- The Scourge of the Underworld is an entire organization of these — though only a scant handful of its victims are actual killers.
- For a time, Morbius would only drink the blood of criminals.
- Frank Miller's Batman. Regular Batman spends his life fearing that he may become this if he ever loses control.
- It could be argued that Rorschach from Watchmen fits in this trope, though he is more commonly placed as He Who Fights Monsters.
- Cassie Hack in Hack/Slash is a former Final Girl who becomes a slasher-hunter. In one of the later comics, she's even referred to by a talk radio host as the "SKK". Samhain doesn't see the difference between her and any other slasher, a sentiment Cassie really doesn't appreciate.
- Andrew Vachss wrote a Predator story where a Predator targeted serial murderers.
- Marv becomes this in the Sin City story, "The Hard Goodbye".
- There's a great early Spawn story where Spawn tracks down a child predator who lures kids to their deaths with an ice cream truck. Spawn then proceeds to kill him by stabbing him to death with ice cream bars.
- Suture from the comic Curse of Spawn.
- The Harris Comics series Twister featured someone who not only slew serial murderers, but did so by twisting their heads around.
- Sinéad Harkin and the servants of Mother Maiden in The Unforgiving (the base for Within Temptation's album of the same name) are very much this.
- In Doctor Who fanfic Gemini, Captain June Harper is a dishonorably discharged former Time Agent now on the run from charges of Police Brutality and vigilante murder. She despises the concept of innocent people suffering, but the Hero Protagonists who travel with her are consistently horrified by the ways in which she kills the people who threaten said innocents. The Lancer Damien claims that the only reason why he and the other heroes support her - even as they are hunted by the universe's law enforcement agencies for aiding and abetting a Super Villain - is because she Hates Being Alone and would just make new friends if she didn't have the heroes. They don't see themselves as supporting June Harper as a serial killer so much as they see themselves as distracting her from starting an army of Serial-Killer Killers.
- A new generation of Assassins in the Discworld of A.A. Pessimal think like this. They are not evil or psychopathic and in many respects are well-adjusted rational people - well, ladies. But this group of Assassins have decided on what they call Ethical Assassination. They still want the money and the contract fees and they respect the rules. Especially the Guild maxim of nil mortifi sine lucre. But they exploit the latitude offered by being able to pick and choose their contacts, and only choose clients whose passing will make the Disc a little bit cleaner. One informal "firm" is dubbed The Marriage Guidance Counsellors, for instance: whatever the reason might officially be, these Lady Assassins choose only men with a reputation for things like wife-beating, rape, child abuse. Then deal with it decisively. A younger Cenotian Assassin takes pleasure in targeting people who get anti-Cenotic. This adds retribution and job satisfaction to her contract fee.
Films — Animation
- The animated movie Justice League: Gods And Monsters depicts an alternate continuity of the DC Universe where Batman, instead of being Bruce Wayne, is Kirk Langstrom, a scientist who accidentally turned himself into a vampire while trying to cure himself from lymphoma (much like Morbius). He deals with the resulting Blood Lust he suffers by feeding on mobsters and psychopaths. Amusingly enough, he is voiced by Dexter's actor.
Films — Live-Action
- Ben O'Ryan in Suspect Zero.
- The title character of The Crow, though not just any serial killer will do. It's personal.
- Zachariah Rigby and his girlfriend Maggie in Seven Psychopaths. They even caught the Zodiac killer!
- The Final Girl becomes one of these in an alternate ending of Captivity.
- In Hard Candy, Hayley turns out to be a variant that targets child molesters rather than serial killers.
- Final Girl: Veronica is specifically raised to ruthlessly hunt down serial killers.
- Agatha Christie's And Then There Were None: U.N. Owen. Except that most of his victims were ordinary murderers rather than serial killers. And, technically, "Owen" would be classified as a spree killer, not a serial killer.
- Hannibal Lecter: Hannibal Lecter, a cannibalistic serial killer with a sizable bodycount of his own, at times goes after other killers when he's not locked up, including Nazi war criminal Vladis Grutas in Hannibal Rising and disfigured pedophile Mason Verger in Hannibal.
- The main character of the novel Bad Monkeys claims to be a member of a secret organization devoted to killing people who are just plain evil and unredeemable. Of course, she could be lying. Or not.
- Philo Vance in The Bishop Murder Case.
- A.J. Holt's heroine Jay Fletcher in the two-novel series Watch Me and Catch Me.
- Jeff Povey's point of view character in the novel The Serial Killers Club manages to be invited into the titular organization after he takes down a serial killer...and begins to kill off the membership, one by one. He says he's not a serial killer himself...but he kills again and again...
- Both Shiki and Fujino in Kara no Kyoukai. This is part of the reason why the part of the story where they fight is the only one where both agonists get out okay, more-or-less. (Well, that and the one where the antagonist has Mind Control to stop Shiki from attacking him...)
- Some of the vampires in Anne Rice's books The Vampire Chronicles tend to be this. Post-Akasha Lestat mostly kills and drinks mobsters, muggers, and the like... but sometimes cannot control himself and kills someone he deems particularly impressive. Another vampire, Pandora, when we meet her, is hunting a drug dealer.
- All of the victims in Regina's Song had criminal records to some degree, but the one the killer was explicitly looking for while she thinned out Seattle's rapist population was a serial killer. At her trial, one of the witnesses remarks that there was a perverse charm in one serial killer dying at the hands of another.
- John Cleaver of the I Am Not a Serial Killer books is this, with the added twist that the killers he hunts are not human.
- The Dexter novels go a bit further than the show — not only do we have Dexter, the two children he's raising are damaged in much the same way he is, and he's trying to teach them to be like him so as to prevent them from becoming even worse.
- Edward Cullen from The Twilight Saga spent a few years killing serial killers during his "rebellious" phase against Carlisle's vegetarian vampirism philosophy.
- The murderer in the Kurt Wallander novel The Fifth Woman turns out to be a rare female example of this trope.
- The narrator of The Rhesus Charts describes Vampire Hunters as this, even making a direct comparison to Dexter.
- In The Girl From The Well, the titular ghost Okiku hunts and kills serial killers who murder children.
- In an ironic twist, Jack the Ripper turns out to be this in one of the epilogues to Alex Grecian's Lost and Gone Forever. Not because he has any moral qualms about the murderer, but because their activities threaten Jack's peaceful retirement.
- Dexter, adaptation of the book Darkly Dreaming Dexter (in season 2, the series took a different direction than the books). Dexter realizes that he's evil, but has been programmed to live within a set of standards that are supposed to place him above common murderers. He sometimes allows himself to fantasize that he is a dark avenger of the innocent. Occasionally, when his target reveals that their victim had it coming too (such as a gay boy who killed his gaybashers before they killed him), Dexter forces his need to go unsated that night.
- In The Inside, the episode "Prefiler"'s titular character, played by a pre-Lost Michael Emerson, profiled potential serial killers, tracked them down before they got a chance to kill, and killed them using their own intended methods.
- Clifford Banks in Murder One is a subversion: although most of his victims were unconvicted serial killers, his first ever victim was his brother, whose murder he forgot and mentally pinned on a burglar. Ironically, this is what led him on the killer-killing path.
- Angel: After Angel gets his soul back, Darla accuses him of being this when he tries to win her back. She says that while he has been killing, it's only been "murderers and rapists." Then she tried to make him kill a baby to prove himself.
- In the very first episode of Tales from the Crypt, "The Man Who Was Death", Niles Talbot is an executioner who was recently fired after the death penalty was abolished in his town. As a result, he goes on a killing spree, killing those who murdered people and escaped justice by various means of electrocution. However, eventually karma bites him in the ass when the tables are turned on him and he is executed using his preferred method just as it was reinstated.
- Madame Vastra, a Silurian living in Victorian London in Doctor Who, eats Jack the Ripper, apparently with Inspector Abberline's blessing.
- An episode of Law & Order: Special Victims Unit has a woman deceive who can't handle that she killed a torturous murderer.
- The 90's revival The Outer Limits (1995) did an episode ("Stitch In Time") where an unbalanced female scientist uses her time machine to go back and execute famous serial killers before they hurt anybody. Her resulting Ripple Effect-Proof Memory does not improve her mental state...
- Hannibal Lecter is an unrepentant serial killer, but he also murders other serial killers such as Tobias, Georgia, and the "muralist" in the course of the show. He subverts this trope, however, since he kills the above serial killers to, respectively, defend himself, to destroy evidence of his own crimes, or to express his artistic side and respect for the killer's work.
- Will Graham has a touch of this trope played straight. Every person he's tried to kill (with or without success) was a serial killer. It's in his job to catch them, but Will enjoys killing in a way that both terrifies and thrills him. It's ambiguous about how much this comes from He Who Fights Monsters and how much is naturally there inside Will.
- In-Universe example in Ash vs. Evil Dead. Ashley Williams has gained quite the reputation as a Serial Killer who leaves bodies dismembered and blasted beyond recognition, all of which is true...except for the fact the people he kills are people or corpses possessed by the Ultimate Evil that gleefully slaughter anyone who gets in their way For the Evulz. Ash himself lacks any traits of a Serial Killer, however, and is more of a Crazy Awesome Dirty Old Man. Lampshaded in the aptly-named "Killer of Killers".
Ash: (having just killed a Deadite in front of the cop convinced he was a murderer) I told you: I kill killers.
- The Forgotten Realms of Dungeons & Dragons have this as the encouraged behavior of the priests of the little-known deity Hoar, Lawful Neutral god of retribution. Specialty priests of Hoar are called Doombringers, and are highly encouraged to kill or otherwise punish (as appropriate for the crime) criminals in a manner befitting the criminal's own misdeeds, especially if they can inflict an ironic punishment.
- Similarly, Mage: The Ascension has the Tradition of the Euthanatos. The Euthanatos view existence as a continual cycle of death and rebirth — "the Wheel" — and those who unbalance the Wheel through atrocities must be dealt with so that things can be set right.
- Werewolf: The Apocalypse:
- The tribal laws of the Black Furies forbid them from turning a blind eye to violence against women. Domestic abusers, sexual predators, and serial killers who murder women are all legitimate targets for them.
- Among the Get of Fenris, the Hand of Tyr camp hunts down those who torment the innocent, including murderers.
- One of the most depraved antagonists in the game is the Seventh Generation, a Wyrm cult that kidnaps children and uses them as human sacrifices. The Seventh Generation's killings and depraved rites have earned it enemies who hunt its members without mercy. For example, the Order of the Rose, an underground organization described in Rage Across New York, hunts down Seventh Generation devotees. Also, one of King Albrecht's first projects after ascending the throne was orchestrating a Garou attack on the Seventh Generation. The result was a slaughter of almost all Seventh Generation members.
- Garou see killing wolves as a grave offense, and some Garou target hunters who slaughter wolves. Several characters in the Warriors of the Apocalypse character book, such as Volcheka Ibarruri and Gere Hunts-The-Hunters, torture and kill wolf hunters.
- In Anathema, your job is to murder people in order to control the global population. Players can choose to act as this. Additionally, if you fail to meet your daily kill quotas enough times, other shrouds will hunt you down and destroy you.
- Geist: The Sin-Eaters: Sin-Eaters mainly focus on dealing with ghosts and helping them move to the afterlife, which in the case of ghosts born from a violent death often means avenging them by finding the one responsible for their murder. Hunter: The Vigil supplement Mortal Remains mentions that Slashers usually are terrified by Sin-Eaters because of this.
- Haseo, the Player Killer Killer from .hack//Roots and Dot Hack GU. Player Killing and Player Killer Killing (ad infinitum) is Serious Business in The World.
- In The Cat Lady, Susan Ashworth's primary goal is to kill five serial killers, called "Parasites".
- The Vigilante alignment in City of Heroes is basically a Hero who kills instead of arrests.
- Serial Killer X from Condemned: Criminal Origins. Spying on FBI Agent Ethan Thomas, SKX figured out the identities of ten other Serial Killers and murdered them in the way they did their victims, which caused them to be confused for their own victims by the authorities and the investigation to go cold, thus keeping X's involvement unknown. In the sequel, his goals have shifted to dissecting people in an effort to give himself superpowers, though it should be noted that while he claimed to have righteous reasons for his killings, he also just really liked getting a thrill out of hunting them down and killing them, and he certainly didn't have any hesitation in killing innocent people, including several of Thomas' fellow officers.
- Dark Souls has the Blades of Darkmoon covenant, which allows you to hunt down and invade players who have been indicted for PvP by doing it too much, cheating at it, or for killing Dark Sun Gwyndolyn, the covenant's leader.
- Matheiu Bellamont from The Elder Scrolls IV: Oblivion. On one hand, he's a murderous lunatic with an incredibly disturbing Torture Cellar cum Room Full of Crazy. On the other hand, he only kills members of the Dark Brotherhood. To make it even more sketchy, he's not even the one that kills a lot of them!
- Pickman from Fallout 4 is a Mad Artist who kills raiders and only raiders. He then uses their blood in paintings and bodies to decorate his rather gruesome gallery.
- James Cash of Manhunt becomes this, technically; he is hunting down and brutally murdering people for Starkweather's Snuff Film, even using slasher-type methods of hunting and butchering, and the people he kills are Starkweather's "workers", which means they're all guilty of multiple murder as well.
- Garrus Vakarian in the Mass Effect series between the first and second games. He became a vigilante in the in-universe Wretched Hive, hunting down all sorts of criminals, often administering poetic justice against the more particularly heinous ones. He brutalized a slaver, killed a drug dealer using the same addictive and deadly drug the dealer sold, killed a specialist in biological warfare with a virus, and killed a dangerous saboteur by causing a space suit malfunction.
- No More Heroes is in part all about this sort of thing. While the player character Travis Touchdown is part of a union of assassins, and as such does get the occasional mission to, y'know, assassinate someone, for the most part his only concern is becoming the highest-ranked assassin in the union by killing off all the higher-ranked ones.
- Alex Mercer from [PROTOTYPE] in a way. He kills thousands of comparatively blameless soldiers to get to their leaders, the ones responsible for the outbreak of the disease ravaging Manhattan, and kill them. His reasoning, insofar as 'reason' factors into anything Alex does, seems to be that however many people he kills, his targets are responsible for both far more deaths and much uglier crimes. Of course, his conscience is still developing throughout the game, so at the beginning he was just a plain-old mass murderer... of guys who were trying to kill him for reasons he didn't understand at that point. (Unless he also killed civilians.)
- In [PROTOTYPE 2], if you don't kill civilians and try to reign in any Marine deaths, then this trope is played straight. Everyone in Blackwatch is evil. Every. Single. Soldier.
- Tormentor from the unreleased fighting game Thrill Kill is a judge executed in the electric chair after it was found out he acquitted criminals just so he could later torture and kill them instead.
- In both MadWorld and Anarchy Reigns, Jack fits this well, and he is very good at it.
- Both Sparkling Justice and Killer Killer from Dangan Ronpa exclusively kill criminals. They may actually be the same person.
- The Onion "Series Of Serial-Killer Killings Rocks Serial-Killer Community"
- Worm: Glaistig Uaine spent much of her pre-teen life hunting down and killing some of the most powerful supervillains on the planet, including Gray Boy.
- The Global Guardians PBEM Universe had The Confessor. The Confessor obsessively hunted down and murdered (usually in a very Karmic Death) other serial killers. When the heroes finally captured him, and one pointed out to the Confessor that he, himself, was a serial killer, The Confessor delivered the Hannibal Lecture to end all Hannibal Lectures.
- The Dove was also a Serial-Killer Killer, but honestly thought he was the hero of his own story.
- If they kill multiple serial killers, wouldn't they be a Serial Serial Killer Killer?