[[caption-width-right:250:[[http://www.pixiv.net/member_illust.php?mode=medium&illust_id=882226 The doctor is in.]]]]

->''"When a doctor does go wrong he is the first of criminals. He has nerve and he has knowledge."''
-->-- '''Sherlock Holmes''', "The Adventure of the Speckled Band"

A Deadly Doctor, simply put, is someone who fights or kills with a medical motif. He uses his medical knowledge to injure, torture or kill, and uses [[ImprobableWeaponUser syringes, pills or surgical instruments]] or medical techniques to achieve his goals. He may wear his labcoat into battle as a BadassLongcoat. Note that in RealLife this would generally be considered a gross violation of medical ethics.

Surely the ultimate example of the MorallyAmbiguousDoctorate. One reason for this is due to all his/her training: while having advanced knowledge on the human body can be used to save people, it also gives all the knowledge on how to injure and kill people with minimal effort by knowing all the body's weak points. Some more sympathetic examples equate to the medical version of a WellIntentionedExtremist, who may certainly have good (or at least sympathetic/understandable) intentions but ruthless medical ethics.

Unless, of course, [[DarkIsNotEvil he's good]]. Which [[NoCureForEvil there is a fairly good chance of]], being able to [[CombatMedic heal as well as harm]].

Note that this trope is ''not'' "Any doctor who is a good fighter." That would be CombatMedic. Deadly Doctor refers specifically to doctors who apply their medical knowledge to their combat techniques.

Can overlap with MadDoctor. May use a HealingShiv, and may even turn them into proper weapons. Compare DepravedDentist and StrappedToAnOperatingTable for cases where medical skill is used as a weapon against a target who isn't in a position to fight back. Contrast MartialMedic, a character who heals with knowledge they gained in the course of learning to injure people. While people do tend to die around him (not his fault, we assure you), [[Series/DoctorWho The Doctor]] is not one of these.

Not to be confused with a doctor who's just dangerously bad at his job; see MadDoctor, BackAlleyDoctor, many instances of DrFeelgood and MeatgrinderSurgery.



[[folder:Anime & Manga]]
* One of the earliest anime/manga examples is ''Manga/BlackJack'', who was known not only as a superhuman surgeon but as a deadly marksman who could kill or, more commonly, incapacitate enemies by [[ImprobableWeaponUser throwing scalpels]].
* Dr. Muraki from ''[[Manga/DescendantsOfDarkness Descendants of Darkness]]''. In the first volume of the manga alone, he turns a dying girl into a vampire and controls her in order to kill people, captures a shinigami and tortures/basically tries to dissect him, and then faces off with Tsuzuki, known as the most powerful of the shinigami, breaking Tsuzuki's spine at one point [[spoiler: and escaping at the end of the book]]. His skill and knowledge as a medical doctor assist him in his various evil endeavors.
* The manga, ''Eliminate Dangerous Doctors'' or EDD is basically this trope being hunted down by a secret agency (which itself may not be as well-intenioned as it may seem, making this a case of BlackAndGrayMorality with the unlucky only good doctor protagonist thrown into the situation).
* ''Manga/{{Gangsta}}'s'' Dr. Theo will not hesitate to drop you with syringe of ''something'' should you threaten his offices or [[AdorablyPrecociousChild cute little apprentice]].
* Palparepa, the BigBad of ''Anime/GaoGaiGar FINAL'', was a clinically white doctor with giant syringes sticking out the back of his mech. He uses them to upgrade himself by sticking his mech with them, a move [[CallingYourAttacks named]] "Doping Cylinder". It's appropriate for a show where the villains' gimmick is super regeneration and TheHero is the "God of Destruction".
* Kuroudo Akabane aka. Dr. Jackal from ''Manga/GetBackers'', who was once a medical doctor tasked with saving lives, but after letting a child die on his watch, decides that he's probably better off [[PsychoForHire mutilating and killing people]] instead.
* Catherine from ''Anime/GregoryHorrorShow''. She is a nurse with a blood-taking fetish and a syringe as big as she is.
* Sanada Kazuki from ''Manga/HajimeNoIppo''. ChickMagnet, genius, and mild-mannered heir [[UnclePennybags to a not-so-mild fortune]]. Did I leave anything out? Well, he ''is'' the one-time national boxing champion and successor to the Hama school of fisticuffs. His style involves rapid calculation of body strength, stun duration, and vulnerable organs and nerve clusters, [[http://view.thespectrum.net/series/hajime-no-ippo-volume-033.html?ch=Volume%20033&pg=ippo_vol-33_116.jpg reforming]] [[http://view.thespectrum.net/series/hajime-no-ippo-volume-033.html?ch=Volume%20033&pg=ippo_vol-33_117.jpg him]] into something of a BadassBookworm in the ring.
* ''VisualNovel/HigurashiWhenTheyCry'' has plenty of perfectly nice people [[spoiler:infected with the HatePlague]] and killing one another in various disturbing ways, but nurse Takano Miyo always seems to be the first to go. Still, further and further into the show, she seems just as creepy as the crazy person of the month if not more so. [[spoiler:Then comes TheReveal, in which she ''engineered'' the whole thing and plans to slaughter the whole town and turn over the virus to military researchers who could use a squad of paranoid people willing to listen to lies and kill their friends...]]
** Also from the series is [[spoiler: Dr. Irie, or at least in his past. More sympathetic than Takano for sure, but in his past was a WellIntentionedExtremist version of this trope.]]
* Dr. Shamal from ''Manga/KatekyoHitmanReborn'' is a doctor/assassin who kills people by infecting them with terminal illnesses from his special mosquitoes.
* Dr. Stanislav Sokurov in ''Anime/MarginalPrince''. While in the first few episodes he only seems to be somewhat [[LargeHam hammy]] and creepy (and [[MadDoctor crazy]]), it becomes clear over the course of the series that he's no ordinary doctor. Then the finale approaches and he goes to take out an entire beach of super-secret assassins. With, of course, a labcoat full of scalpels.
* ''Manga/{{Naruto}}'':
** Kabuto, who uses the medical knowledge he picked up as a longtime mole to do incredible damage to others' bodies.
** Tsunade can use her knowledge of the human nervous system to [[InterfaceScrew flip around muscle coordination]] so that moving your left leg moves your right arm and vice versa.
** A little more subtle example earlier in the series is Haku, and thus, by extension, ninja that have ANBU training--though we don't see most of them really use it. He puts Zabuza into a fake death state with a thrown needle in order to trick Team 7. Later, in the bridge battle, he specifically only targets Sasuke in non-vital areas in an attempt to dissuade and not kill him. The obvious implication is that he could have gone for fatal shots from the start if he so chose.
* ''Anime/NurseWitchKomugi'' is a medical-themed MagicalGirl. She started as Komugi Nakahara, a deranged mutant nurse with a fetish for oversized medical equipment (especially needles) in the much darker anime ''Anime/TheSoulTaker''.
* ''Manga/OnePiece'' has two notable examples.
** [[TalkingAnimal Tony Tony Chopper]] isn't particularly malicious, so he usually uses his medical knowledge to fight through consuming a special medicine he made for himself called the Rumble Ball that improves his shapeshifting abilities. After the TimeSkip, he can use it to control himself in his [[AttackOfTheFiftyFootWhatever Monster Point]]. He's also used his knowledge of anatomy to point out how to break a zombie's spine, since it was already dead.
** And Doc Q of the Blackbeard Pirates; When we first meet him, he's giving away apples…some of which ''explode'' when bitten, and later learn that his nickname is "Death God". During the Paramount War, he wields a SinisterScythe. All while being quite sickly himself.
** Then there's Trafalgar Law, also known as "[[RedBaron The Surgeon Of Death]]." Which is odd, to say the least, looking at him. He has the power of the Ope-Ope Fruit, which allows him to cut anyone or anything within a certain range and rearrange the pieces as he sees fit. People don't die when cut up this way, allowing him to extract organs, remove poison and even attach new body parts without putting the person in question at risk. Smoker even compares the power to that of being placed on an operating table.
*** It's worth noting that Law's Devil Fruit is unique because medical knowledge is actually ''required'' to be able to use it to it's utmost potential. Law's exceptionally rich background in the medical field is very evident, as he uses his abilities granted by the Ope-Ope Fruit to remove bullets from his own torso, discharge electricity from his hands like defibrillators, and then there's his most devastating technique 'Gamma Knife', which uses a conjured blade of screeching ''gamma radiation'' to reduce his victim's internal organs to sludge, leaving no visible evidence of trauma on their bodies.
* One MonsterOfTheWeek of ''Anime/PhantomQuestCorp'' is a doctor who made a DealWithTheDevil so he can murder patients and harvest their organs for sale (magically concealing the evidence). He got some sort of demonically-possessed superpowers as part of the bargain as well, and tosses scalpels and manipulates a laser surgery machine telekinetically, or as the dub has it:
-->'''Lieutenant Karion:''' Psychokinesis?\\
'''Ayaka Kisaragi:''' Or just psycho!
* ''Anime/{{Pokemon}}'': Dr. Proctor from the Indigo saga, who fought Team Rocket armed with nothing but a labcoat full of scalpels.
* ''Manga/RosarioToVampire'' has one of the hybrids posing as a nurse. She can control her victims with some kind of poison.
* ''Anime/SailorMoon'' had two medically-themed [[MonsterOfTheWeek monsters of the week]]: Pharmakon and Sailor Doctor. Both had a giant syringe replacing one arm.
* Faust VIII from ''Manga/ShamanKing''. He could use his medical knowledge to take down enemies and even survive falling out of a plane in a wheelchair without a parachute. Although considering he's a necromancer, it may be that his body is mostly dead anyway and he simply needed to locate any lost limbs after landing. That and he's on a ''lot'' of morphine.
* ''Manga/SoulEater'' has two notable characters who fit this.
** Nygus. School nurse a d BandageBabe. And she's also a commando and [[EquippableAlly as a weapon]] can turn into a knife.
** Stein, for that matter. The best teacher in the academy and a dangerous man, he can use his knowledge of soul wavelengths to disrupt others' attacks and empower his own. He also has vast experience both in efficiently cutting things apart and suturing them back together to cleanly heal - and ''both'' of these skills are weaponizable.
* In ''Manga/SteamDetectives'', the black-clad nurse Lang-Lang who serves Boy Criminal Le Bledd [[EvilCounterpart the same way]] the white-clad nurse Ling-Ling serves Boy Detective Narutaki, the hero of the series. Lang-Lang began trying to heal people, but decided it was easier to end their suffering by killing them; she likes the idea of preserving handsome young men/cute boys via taxidermy "so they stay young for ever!" [[spoiler:Oh, and she is Ling-Ling's sister, though not an actual twin...]]
* The school nurse Ayukawa/Fonda Fontaine from ''Anime/YuGiOhGX'' is a pretty decent girl and an excellent healer, normally, but after she's turned into a [[ZombieApocalypse Duel Ghoul]] in the first half of the third season, it's revealed she has a deck that caters to this theme, giving you life points while using cards that turn that gain into damage. Not surprisingly, her key card in that deck, Nurse Reficule the Fallen One, is a demonic nurse wrapped in bandages.
* Minoru "Doctor" Kamiya of ''Manga/YuYuHakusho'' fights with hands that cut like scalpels, and insects with syringes that inject diseases into his victims.

[[folder:Comic Book]]
* ''Franchise/TheDCU'':
** The Mikado, a foe of Comicbook/TheQuestion, was an emergency room physician who was disgusted by some of the deliberately inflicted injuries he saw in his ER. He donned a costume and used his medical expertise to inflict similar injuries on those responsible.
** The Crime Doctor.
** Dr. Moon, who considers himself [[TortureTechnician an artist when it comes to pain]]. He's also a self-taught medical genius who uses his incredible talent to cause suffering rather than heal.
** Hush of the Franchise/{{Batman}} comics evolves into this after he drops the guntoting. Scarecrow also counts, having been the head psychiatrist at Arkham.
*** Let's not forget Hugo Strange, one of the few villains to successfully uncover Batman's true identity.
*** Harleen Frances Quinzell was a psychiatric intern. She has a PhD.
** Even heroes with medical doctorates have been known to use their skills to incapacitate people as Dr. Mid-Nite from ''ComicBook/JusticeSocietyOfAmerica''.
* ''Franchise/MarvelUniverse'':
** [[StevenUlyssesPerHero Angeline Kutter]], [[http://marvel.wikia.com/Angeline_Kutter_(Earth-616) The Surgeon General]] who fought Comicbook/{{Daredevil}}.
** [[UsefulNotes/TheGoldenAgeOfComicBooks Golden Age]] superhero, and later member of the ComicBook/XMen, Doctor Nemesis.
* In [[PolishMedia Polish graphic novel]] "Żyjesz?" ("Alive?") a [[PlagueDoctor Plague Doctor]] stabs a tie-to-the-bed patient with the knife in the chest when he starts screaming. Another doctor get killed by his fellow medic after being bitten by a contain boy. During the climax of the book one more doctor is attack by armed lunatic and he just shots him in the face with a pistol.
** It's should b noted that all the doctors in the book are mysterious and scary figures and we never see their faces.
* Ratchet, in the ''ComicBook/TransformersShatteredGlass'' universe. Being in his care is more of a punishment than a treatment, as he tends to whimsically replace his patients' body parts with whatever he thinks would look better.
* In ''ComicBook/{{Violine}}'', the doctor (no name given) uses his medical skills to restrain Violine (by putting her legs in casts, pretending they are broken), and later attempts to make her sick and bedridden to get her to go home. Eventually, he attempts to outright kill her with poison when all else fails. [[spoiler: It is later revealed that he killed his father's parents as well]].

* [[BewareTheNiceOnes Haku]] in the ''Manga/{{Naruto}}'' fanfic FanFic/{{Hakumei}}. After apprenticing to a medic-nin for some years, his fighting style incorporates drugs and poisons, and while he doesn't ''like'' hurting people, he's ruthless when he has to be. His friends would say that he's the scariest member of their group.
* ''FanFic/WinterWar'' (a ''Manga/{{Bleach}}'' AU where [[TheBadGuyWins Aizen won the war]]) has Ogidou, a former Fourth Division member who fights by reversing healing kidou. For example, one of his attacks reopens old wounds that have scarred over. The other members of LaResistance let him do it, but find it disturbing. Hinamori, who's part of the same small group of fighters, refuses to let him heal her, even though she acknowledges that he's competent.
* Though Dr. Watson is definitely a MartialMedic, he plays the DeadlyDoctor trope [[BewareTheNiceOnes frighteningly straight]] in the ''Fanfic/DeliverUsFromEvilSeries''.
** ''"If your master's actions destroy him whom I regard as-as the best and wisest man I have ever known-make no mistake that I shall hunt down, to a man, everyone who played a part in his destruction."''
* This trope is briefly referenced in ''FanFic/ChildOfTheStorm,'' speaking about [[MamaBear Branwen Hufflepuff]], ancestress of Helga, who was usually a very gentle and loving healer, but used her skills for the exact opposite when her daughter was assaulted, tortured, and killed by Frost Giants. [[spoiler: Doctor Essex]] is also a mix of this and EvilutionaryBiologist, who regards the world as his petri dish and uses his advanced knowledge of human genetics to perform all sorts of monstrous acts.

* Elle Driver disguised herself as a nurse in ''Film/KillBill'' in order to carry out a hit on The Bride with a poison syringe, only to have her mission canceled by Bill himself. Since Elle despises the Bride, she does not take it well.
** The scene was based on a similar one from ''Film/BlackSunday'' – in that case it was successful.
* ''Film/RepoTheGeneticOpera'' has the Repo Men, trained medical professionals who mostly do their deadly work with scalpels and bloodproof surgical gowns, and the Genterns, who, while they don't kill people nearly as often, can be pretty damn sinister.
* ''Film/{{Ghostbusters 1984}}'': Egon Spengler states that Ivo Shandor, also the architect behind ''that'' building, was one of these due to unnecessary surgeries.
* ''Film/TransformersRevengeOfTheFallen'' features the Doctor, a tiny Decepticon surgeon charged with planting mind probes in victims.
* One fight in ''Film/SherlockHolmes2009'' had ''Doctor'' Watson say "I'm a doctor" to the guy he has in a choke hold. He also looks better at fighting than Holmes is. Makes sense as Watson is a trained soldier, and Holmes only really gets amazing when he's had a chance to calm down and analyze his opponents carefully.
%%* Creator/MelBrooks' character in ''Film/TheMuppetMovie''.
%%* Dr. Christian Szell in ''Film/MarathonMan''
* Dr. Albert Hirsch from ''Film/TheBourneSeries'', responsible for creating and running of Treadstone/Blackbriar black ops projects where, via brainwashing, torture and behavioral conditioning they turned volunteers into tools ready to kill on command.
* Dr. Kaufman in ''Film/TomorrowNeverDies'', a hitman who uses his forensic medicine expertise to cover his tracks.
* Main villain of ''Film/TheDeadPit'' is an undead former surgeon of a mental hospital who with his zombies seeks out to remove everyones brains.
* ''Film/EscapeFromLA'' gives us the Surgeon General, played by a wonderfully [[LargeHam hammy]] Creator/BruceCampbell.
* The eponymous ''Film/DrGiggles'' uses typical doctor's equipment to kill his victims. This includes such things as syringes, an otoscope and a sphygmometer.
* ''Film/ReturnToHouseOnHauntedHill'' has the ever-so-evil Dr. Vannacutt.
* The evil medical staff abduct people, kill them and steal their organs in ''Film/TheXFilesIWantToBelieve''.
* The Stitch class of psychics in ''{{Film/Push}}'' are nominally healers (and damn good ones at that). They can completely heal bones and the like by laying their hands on a person. However, they can easily use their medical powers to ''break'' bones and stir up a person's insides as well. God forbid a malevolent Stitch gets their hands on you...
* In ''Film/PansLabyrinth'', the doctor [[spoiler: who secretly helps the rebels]] is a non-combatant. However, at one point, he applies his medical knowledge to [[spoiler: mercy-kill a captured rebel after being called to keep him alive for more torture.]]
* ''Film/CloudAtlas'': Henry Goose, though [[spoiler:Ewing eventually doubts that he was anything more than a murderous confidence trickster]].

* There aren't Water Knights in ''Literature/CodexAlera''; normally they're just the medics. Now, they're latently empathic medics, so they actually get a significant good feeling from reducing the pain and misery in their presence, meaning they're unlikely to use their powers as a weapon. But, remember, ''most of your body is water''. Are you afraid yet?
* Annie Wilkes in Creator/StephenKing's ''{{Literature/Misery}}''.
* The nurse assassin from ''Literature/{{It}}''.
* From the ''Franchise/StarWarsExpandedUniverse'':
** Ton Phanan from the ''[[Literature/XWingSeries X-Wing]]'' series, who was a doctor before [[CyberneticsEatYourSoul cybernetics ate his future]] and he became a pilot-medic. At one point he cuts a man's throat using a laser scalpel, and notes that anything in his medical kit can be weaponized.
-->'''Interrogating Colonel''': "Did you surrender this weapon to ''our'' guards before coming before me?"
-->'''Phanan''': "What weapon, sir?"
-->'''Interrogating Colonel''': "The laser scalpel."
-->'''Phanan''': "Not a weapon, sir. It's a tool of medicine. I wasn't asked to turn over my bandages, bacta treatments, disinfectant sprays, or tranquilizers either, but I can kill a man with any of them, under the right circumstances."
** And Mij Gilamar, from the ''Literature/RepublicCommandoSeries''. His medical knowledge is considerable, but add to that the fact that he's the very definition of a CombatMedic, fully trained as a [[ProudWarriorRaceGuy Mandalorian]] soldier, and you've got someone who can just as easily put you together as take you apart. Though normally a very kind, and even somewhat charming man, when asked about why he wears the Mandalorian color of vengeance on his armor, he has ''this'' to say:
--->'''Gilamar''': "I fell in love with a Mandalorian girl, married into the clans, and a ''hut'uun'' killed her. I know his name. I'll find him. And then I'll show him what it means to make a bad enemy of a Mandalorian with anatomical expertise and a scalpel."
* The ''Literature/HeraldsOfValdemar'' series once states that the same Healers who can stop the pain and put you together also know how to take you apart, so it's unwise to anger them.
* In the ''Franchise/SherlockHolmes'' short story "Literature/AStudyInEmerald" by Creator/NeilGaiman, the Great Detective remarks, concerning his deduced perpetrator of a brutal murder, "[I]t is my experience that when a Doctor goes to the bad, he is a fouler and darker creature than the worst cut-throat." [[spoiler: Of course, the reader is more likely to agree with Dr. Watson on the rightness of his actions, making this a subversion.]]
** This quote is inspired by the actual Literature/SherlockHolmes calling a doctor "who goes wrong" the "first of criminals" in "The Adventure of the Speckled Band".
** In the original-canon story "The Adventure of the Dying Detective", the villain is an doctor who sends Holmes a package booby-trapped to infect him with a deadly disease. The trap fails, but Holmes lets him think it succeeded in order to lure him into [[EvilGloating gloating]] and [[EngineeredPublicConfession admitting his guilt]].
* "Dr. Danco", who slices and dices his victims, in ''[[Series/{{Dexter}} Dearly Devoted Dexter]]''.
* In "Melanie and Merrick", Nurse Katie Heller, who has Manchausen Syndrome by Proxy, uses her medical knowledge of medicines to kill off patients, sometimes even swapping their prescribed medicine with a deadly substance. Her ultimate plan to kill off the Elephant Man fails heavily, and her ass is kicked hard by the hospital's scrubber, [[FieryRedhead Melanie Bell]]. Naturally, Katie is fired.
* In Literature/TheFatherLukeWolfeTrilogy, Dr. Brandt scratches Father Wolfe's wrist with a nicotine-filled syringe as a "reminder" to give his son a passing grade. He also threatens that worse than nicotine would have been an empty syringe, since a bubble of air in the bloodstream can jolt the heart into stopping. [[spoiler:It turns out this is how he murdered his colleague earlier.]]
* In Creator/AaronAllston's ''Literature/GalateaIn2D'', Medea was designed for this. She both designs the poison to use on Red, and its antidote. And it is Roger, not Medea, who has scruples about it.
* In ''Literature/TimeScout'', UsefulNotes/JackTheRipper is a rather well known physician.
* Dr. Peter Brown, from ''Beat the Reaper.'' [[spoiler: He used to be a hitman. Now he's in witness protection.]]
* In ''Literature/DocSidhe'', Alastair explains that his world's equivalent of the Hippocratic Oath only applies to his patients -- and the guys he shoots aren't patients until ''after'' he shoots them.
* In ''Literature/TheGolgothaSeries'', Golgotha has bad luck in this regard with their doctors. Their current doctor, Dr. Francis Tumblety, is a racist and sexist quack who is only tolerated because the town's previous two doctors turned out to be murderous monsters. His predecessor was a monster which [[TakenForGranite turned people to stone]] and drank their memories, and the one before that was some sort of creature which had to be staked through the liver and buried under the railway tracks. [[spoiler:And Dr. Tumblety ends up continuing the streak, as he turns out to be Jack the Ripper]].
* The infamous Dr. Hannibal Lecter, created by Thomas Harris befits this incredulously. Other than application of his medical knowledge to terrorize and torture his victims, he also uses this to hunt, when it's not humans. Methods of torture inclusive of anaesthetization, and skull trepaning for death realization with the doctor in sight.
* ''Implant'' by Paul F. Wilson provides Dr.Duncan Lathram. A disgruntled physician done wrong by the helms men of the medical profession. [[spoiler:His vengeance is a harmful concoction embedded in the kakistocracy's bodies once they seek his face lifting and beautification surgeries]].
* ''Literature/JoePickett'': Dr. Eric Logue in ''Trophy Hunt''. A former army surgeon, he was dishonorably discharged from the army and sent to a military prison for conducting unnecessary surgery on prisoners of war. Escaping, he travels the country posing as ufologist; attacking and dissecting people while they are still alive.

[[folder:Live Action TV]]
* ''Franchise/StarTrek'':
** In Seska's reprogrammed version of ''Series/StarTrekVoyager'', the holographic doctor loves to hurt people instead of healing them. It can inject you with acid instead of medicine.
** In the ''[[Recap/StarTrekS2E4MirrorMirror Mirror, Mirror]]'' MirrorUniverse, ''Series/{{Star Trek|The Original Series}}'' doctors get rather upset when they find out what their {{evil counterpart}}s do in that universe.
** Same MirrorUniverse, different series: in the ''Series/StarTrekEnterprise'' episode "In a Mirror, Darkly" we see Mirror!Phlox smiling cheerfully... while torturing an alien.
** Vidiians in ''Series/StarTrekVoyager'' are an entire race of these, using their medical knowledge to steal organs to ensure their own survival. Their weapons double as medical devices.
* A MonsterOfTheWeek on ''Series/{{Charmed}}'' is Doctor Williamson, and infectious disease specialist who had treated Piper when she was sick a few episodes earlier. He's a good guy, but when he accidentally injects himself with Piper's blood, he also gets her powers. Turns out mortal + powers = CRAZY. He goes on a killing spree and takes organs from people. [[spoiler: Piper eventually has to kill him to stop him, which she finds very hard to do, as he is the first human she ever killed, and he tried to save her life.]]
* Series/{{Dexter}}'s first kill is of a homicidal nurse, who overdoses patients in her care that she considers to be in too much pain to keep living.
** For that matter, Dexter himself attended med-school before becoming a blood spatter analyst. This explains his surgical killing style and familiarity with anatomy and pharmacology.
* On ''Series/{{Supernatural}}'', one of the [[MonsterOfTheWeek Monsters of the Week]] was a doctor who had managed to make himself immortal and was taking other people's organs when his gave out.
* More than one episode of ''Series/LawAndOrder'' has featured doctors who killed patients deliberately (many more have featured doctors who killed by negligence).
* ''Series/FridayThe13thTheSeries'' featured two doctors who had cursed antiques (a scalpel and a Native American shamanic rattle) that could heal people... as long as they were first used to kill.
* An episode of ''Series/{{Farscape}}'', "DNA Mad Scientist" had a highly intelligent alien doctor who was always performing experiments on aliens to increase his powers.
* This trope makes up the plot of ''Series/TheXFiles'' episode "Sanguinarium".
** Evil doctors also make appearance in several MythArc episodes. They have no scruples about performing horrible experiments on people. Often it's blurred whether it's aliens or the conspiracy. Or it might be both.
* Subverted in ''Series/BakuryuuSentaiAbaranger''. Dr. Yukito Sanjou/Abare Blue is a chiropractor who doesn't bring its expertise in battle, but when he actually does chiropracticing, it was ''extremely painful'' (though you'll feel better afterwards) that could make even battle-hardened veterans wince in pain. Then there's Dr. Mikoto Nakadai, who didn't quite bother bringing his medical expertise in battle or whatever, but considering his [[SuperSpeed battle]] [[HeroKiller capabilities]], and his [[ForTheEvulz motivation]]... he's deadly on his own.
%% * [[Series/DoctorWho The Doctor]]. The Oncoming Storm, the Bringer of Darkness, the only person to scare man-eating shadows, killer snowmen, and Daleks alike.
* In the crossover with ''Series/NinpuuSentaiHurricaneger'', Yukito did use his chiropractor knowledge to crush the monster of the movie's bones... ''unmorphed''. [[spoiler:(it's just a clone though)]]
* ''Series/{{CSI}}'''s Doctor Jekyll. He used surgical means to kill his victims, like the guy who got an infected appendix sewn into him.
* The Surgeon, a SerialKiller on ''Series/RizzoliAndIsles''.
* ''{{Series/Highlander}}'' had a villain of the week who was a slightly mentally unstable doctor who got fixated on Duncan after he witnessed evidence of his immortality. He'd been kidnapping and experimenting on other patients before that as well.
* On ''Series/AmericanHorrorStoryAsylum'', it's revealed that Bloody Face's victims were killed with surgical precision. That's because [[spoiler: Bloody Face is really Dr. Oliver Thredson. As a psychiatrist and licensed doctor, he would have had the surgical training necessary to commit his crimes.]]
* [[AnIcePerson Killer Frost]] in ''Series/TheFlash2014'', as she's [[spoiler: the SuperPoweredEvilSide of Dr. Caitlin Snow, the team's [[TheMedic medic]]]]. In the episode [[Recap/TheFlash2014S3E7KillerFrost "Killer Frost"]], she uses her anatomical knowledge to sever [[Comicbook/TheFlash The Flash's]] leg muscles so she can escape him.
* Skye's father in Series/AgentsOfSHIELD. He's a former volunteer for Doctors Without Borders, but after violently separated from his wife and daughter by Comicbook/{{HYDRA}}, his willingness to [[TheUnfettered go to any lengths]] to get his family back, combined with his experiments with a PsychoSerum has left him a little... [[AxCrazy unstable]].

* In ''Music/ToKeepMyLoveAlive'', the narrator has one husband from a sanitorium, who needed various medicinal drinks. Her drink, however, wasn't exactly curative.

[[folder:Newspaper Comics]]
* Dr. Plain from ''ComicStrip/DickTracy''.

[[folder:Professional Wrestling]]
* In the territory days, Dr. Sam Sheppard (who may or may not have inspired ''Series/TheFugitive'') became a wrestler in his later years, exploiting his extensive anatomical knowledge to great effect in the ring through the use of {{Pressure Point}}s.
* [[Wrestling/{{Kane}} Isaac Yankem, DDS]], from early-1990s Wrestling/{{WW|E}}F, back when [[WrestlingDoesntPay everybody had a second job]].
* Wrestling/KaijuBigBattel's resident surgeon and usual BigBad Dr. Cube. He destroys by appointment.

[[folder:Tabletop Games]]
* The [[OurOrcsAreDifferent Orks]] of ''TabletopGame/{{Warhammer 40000}}'' have "Mad Doks" or "Painboyz" to keep the lads on their feet during battles, and who occasionally put their bonesaws and "'Urty Syringes" to offensive use (the latter is an actual piece of wargear that does poisoned attacks). Since the specialists in question are [[MadScientist mad scientist-esque]] physicians with an instinctive (if imprecise) grasp of medicine and an urge to "tinker," they count as Deadly Doks ''off'' the battlefield, too.
** The main job of SpaceMarine Apothecary is to keep their battle-brothers alive and collect the gene-seed of the dead, but being an 8-foot-tall genetically enhanced {{Super Soldier}}s in PoweredArmour, they can and will kick ass if necessary. Not to mention that using the gene-seed extractor on a living person is going to hurt.
---> "[[VideoGame/DawnOfWar Death or healing, I care not which you seek!]]"
** [[CrazyAwesome Mad Dok Grotsnik]], the most famous of all Painboyz, is also the deadliest of all. Far smarter than the average Ork, he's always in the [[strike:ranger's]] Nobz' [[strike:hair]] heads, or rather he puts [[ExplosiveLeash remote detonated bombs]] [[YourHeadAsplode inside their heads]] just in case they try anything funny.
** Haemonculi, the Dark Eldar's medical scientists (i.e. {{Torture Technician}}s), also tend to wear combat gear heavily inspired by labcoats and surgical scrubs. Sometimes that's made of GenuineHumanHide too.
** The Sisters Hospitaller of the Imperium. While their focus is primarily on medical support, they are also skilled at torture. The Ecclesiarchy sourcebook for ''Dark Heresy'' states that Inquisitors are taught to never trust medical care for imprisoned traitors or heretics to Hospitallers. No matter how much an Inquisitor may insist their captive needs to be kept alive for the moment, Hospitallers are so zealous that they are far too likely to "accidentally" lose the patient's life.
* TabletopGame/{{Eberron}}'s House Jorasco focuses on healing (and, thanks to the power of their Dragonmark, has managed to severely cut down the temples' share of the magical healing market), meaning an adventuring Heir would have some aspects of this trope by default. The [[WikiMagic Jorasco prestige class added by the Dragonmarked sourcebook]] fits it even better, as it models a secret sect within Jorasco that turns their healing powers to the art of diseases (as in, ''causing'' them) and harm. Given that they have to be non-good, the best case scenario is an AntiHero.
* Surprisingly subverted by Yawgmoth in ''TabletopGame/MagicTheGathering''. Despite being the BigBad, he was a very skilled doctor and, even if his cure for phthisis wasn't seen well, it actually worked. Even when he started adding massive doses of BodyHorror, his target was always to ''improve'' his patients, not to murder them.
* The Doctor career archetype in ''TabletopGame/HunterTheVigil''.
* ''TabletopGame/YuGiOh'':
** The demonic [[http://yugioh.wikia.com/wiki/Nurse_Reficule_the_Fallen_One Nurse Reficule the Fallen One]] in the (used by a nurse character in the anime, as mentioned above) is this. Her effect turns any effect that restores Life Points into one that causes Effect Damage. (Basically, she does exactly the opposite of what a nurse is supposed to do. Given the fact that she's a FallenAngel, it's no surprise.)
** [[http://yugioh.wikia.com/wiki/Injection_Angel_Lily Injection Fairy Lily]] looks friendlier, but is no less deadly. If the player pays 2,000 Life Points during a battle, her Attack Score rises by 3,000 points, making her strong enough to defeat even a Blue-Eyes White Dragon.
* The Medic in ''TabletopGame/FengShui'' can be one of these quite easily, though most tend toward the CombatMedic archetype.

[[folder:Video Games]]
* The medic class from ''VideoGame/DirtyBomb'' are great combatants in their own right. Though they primarily use guns to kill, they also have [[MagicalDefibrillator defibrillators]] that can revive downed teammates and [[HealingShiv zap enemies]].
* Both {{Big Bad}}s of the ''VideoGame/KillingFloor'' series, Dr. Kevin Clamely (The Patriarch) and Dr. Hans Volter, engineered the hordes of monstrous specimens the player faces. Clamely in particular ran Horzine, the largest pharmaceutical company in the game's world, and Volter in particular puts medical (mal)practice into his combat style.
* Meddy from ''VideoGame/MegaManBattleNetwork 5 Team [=ProtoMan=]'' is a nurse who throws bombs shaped like pills.
** And that doesn't cover the manga, as she [[http://www.mangahere.com/manga/megaman_nt_warrior/v10/c006/3.html knocks TomahawkMan out of her way]], then [[http://www.mangahere.com/manga/megaman_nt_warrior/v10/c006/4.html she picks up and throws MegaMan on the ground]], and when he tries to talk Colonel into letting him go [[http://www.mangahere.com/manga/megaman_nt_warrior/v10/c006/5.html she stabs him in the butt with a giant syringe]].
* In ''VideoGame/KnightsOfTheOldRepublic'', the Heal Force power is closely related to the Wound power. Every Jedi in both games can end up with both.
* The Medic in ''VideoGame/TeamFortress2'' can be pretty deadly with the bone saw if you can get close enough. Or his ''syringe gun''.
** He's got decent, self-regenerating health, a good running speed, has an alternate syringe gun that drains health, can heal at range, [[LimitBreak make his healing target and himself invulnerable]], and has [[http://wiki.teamfortress.com/wiki/Ubersaw this]] as his alternate bonesaw. Even his backstory as a psychotic MadScientist fits the bill. And then there's his TFC equivalent, who was more or less a full combat class with the ability to heal people.
** To drive the point home, [[HypocriticalHumor one of his melee weapons is a bust of Hippocrates' head with a "Do No Harm" plaque]]. Which he uses to beat people to death with.
*** It explains a lot about his personality and style that he was trained in medicine [[UsefulNotes/NaziGermany in a time and place]] where the Hippocratic oath was downgraded to a ''Hippocratic suggestion''. And an ''optional'' Hippocratic suggestion at that.
* Conversely, the Healer [[AnAdventurerIsYou character class]] in ''VideoGame/NetHack'', while having mostly magical healing abilities, begins with a scalpel as their melee weapon.
** But is also the best class available for pacifists.
** Speaking of which: all of the nurses in ''VideoGame/NetHack'' will try to kill you. [[spoiler:Unless you remove all armor and weapons, in which case they will raise your maximum HP instead.]]
* Anesthesia/Dr. Cutter from ''VideoGame/RumbleRoses''.
* Faust of ''VideoGame/GuiltyGear'' fame is a 9-foot-tall doctor who wields a scalpel as big as he is. Bonus points in that he actually ''heals'' people as well as kick ass, and kicks ass in order to stop people from getting hurt in the first place. Now that's what ''I'' call, aggressive vaccination.
** Doctor Baldhead from the first game was far less pleasant. After accidentally killing a patient, he went insane and became a serial killer, murdering under the delusion of healing. Then he met the ghost of his patient, and learned it wasn't his fault. He hid his face under a paper bag, became TheAtoner, and that's where Faust came from. (It's confirmed at several points in the series's Story Modes.)
* Kyoko Minazuki from the ''VideoGame/RivalSchools'' series, who serves as a school nurse when she's not cracking skulls.
* ''VideoGame/ViewtifulJoe'' has nurse EliteMooks with giant needles or scalpels.
* The demonic nurses in ''Franchise/SilentHill''. [[VideoGame/SilentHill1 The first game]] also had doctors.
* ''[[VideoGame/SuperSmashBros Super Smash Bros. Melee]]'' and ''[[VideoGame/SuperSmashBros Super Smash Bros. 4]]'' have Dr. Mario, who throws giant vitamin capsules as his standard special attack. One of his alternate costumes (the [[DarkIsEvil black one]]) is sometimes exaggerated as one of these in fanon.
* Dr. Schabbs, the Episode 2 FinalBoss in ''VideoGame/Wolfenstein3D''. He wore a lab coat and was armed with a needle filled with the "poisonous corpsokinetic animation serum" he used to create his mutant zombie soldiers.
** Wilhelm "Deathshead" Strasse from ''VideoGame/ReturnToCastleWolfenstein''.
* Dr. Vahzilok from ''VideoGame/CityOfHeroes'', who uses his modern scientific equipment to conduct strange, ''forbidden'' experiments... on himself as well as others.
** Plenty of player characters as well, with the Pain Manipulation power set being very well suited for it thematically.
* Plastic surgeon Dr. Steinman from ''VideoGame/{{BioShock|1}}''. Bonus points for the fact that he thinks he's [[MadArtist the Picasso of surgery because he's abandoned concepts like symmetry]]. The other splicer doctors in the game are also terrifying. They have spot-on voice acting, evoking hard-nosed medical authority raised to insanity. They have some ghastly good lines, too: "I hate the babies the most. They come out covered in death."
* Doctor Theolen Krastinov, TheButcher from ''VideoGame/WorldOfWarcraft'' probably fits with his goggles and gloves. Of course, the medical implements he attacks you with are bloody meat cleavers.
* The Backstab Master in ''VideoGame/{{Arcanum|OfSteamWorksAndMagickObscura}}'' is a doctor who fled the city after stabbing a man to death with a pen. Unsurprisingly, the training he gives you involves medical expertise on most vulnerable parts of human (elf, dwarf etc.) body. [[ChronicBackstabbingDisorder What he does after training you is likewise no surprise.]]
* Dr. Redmoor of ''VideoGame/DementiumTheWard'', who also has traces of MadScientist.
* In the ''VideoGame/{{Fallout}}'' games, there is a perk (Living Anatomy) which gives you a bonus to medical skills, but also, due to your mastery of anatomy, raises your base damage against living opponents.
** More of an example being your Father in ''VideoGame/{{Fallout 3}}'': He just, ''on a whim'', decides to escape a secure vault, cross the wasteland from one side to the other with no companions (a feat replicated only by your stupidly powerful character) and no armament except a ''hunting rifle''. He then proceeds to enter and leave a super-mutant infested building (unwounded!) and then a mind-control simulation pod before he [[spoiler: calmly sacrifices himself in an attempt to wipe out the leader of the Enclave assault on the Capital Wasteland.]] He is a badass doctor like no other.
* Mordin Solus from ''VideoGame/MassEffect2'' averts the trope. He's an extremely skilled doctor as well as a complete badass, but he'd '''never''' kill anyone with medicine. Nonetheless, while people are thankful for his medicinal work, the fact that he takes lives as easily as he saves them utterly terrifies more than a few who know of him.
** Played with; the fact that [[spoiler:he was part of the STG team that developed and deployed the second version of the genophage]] gnaws his conscience hard. He tries hard to justify his actions, but [[spoiler:millions of unborn krogan children and the cultural and emotional heavy decay the krogan, as a race, suffer]] are a heavy burden to carry, as Maelon wisely points. And it's a major plot point on his character development.
-->"Have killed many people, Shepard. Many methods. Gunfire, knives, drugs, tech attacks. [[NoodleIncident Once with farming equipment.]] But not with medicine."
-->"Many ways to help people. Sometimes cure patients. Sometimes execute dangerous individuals. Either way helps."
* ''VideoGame/{{Touhou}}'''s Eirin Yagokoro is often depicted as this by fans.
* A large amount of modern {{MMORPG}}s that have a [[WhiteMage healer class archetype]] will allow, to greater or lesser extent, the player to choose skills, stats and/or gear to make them more offensive than defensive. Whilst a viable tactic in most cases, there will always be fallout from the... "purists" who will [[StopHavingFunGuys insist that healers heal]] and that anyone not playing them straight is a {{Scrub}} and wasting the time of all concerned. Potentially the basis for realtime {{FlameWar}}s.
** In some cases, such as ''Cataclysm''-era ''VideoGame/WorldOfWarcraft'' design, healers are ''encouraged'' to do a certain amount of attacking (usually because it provides bonuses to their subsequent healing), on the theory that [[ComplacentGamingSyndrome 24-7 healing with no variation]] can get incredibly boring and [[RuleOfFun they're better off with a more varied toolkit]] that forced them to adapt to different boss fights the way damage-dealers do.
* The ''VideoGame/EtrianOdyssey'' series' Medics can be powerful front-line fighters, the exact opposite of their intended role as fragile healers. This requires very deliberate skill-tree set ups but is surprisingly practical.
** In addition, both of the healing classes in ''Etrian Odyssey III'', the Prince(ss) and the Monk, have fairly potent combat ability, especially the Monk, and ''especially'' once you unlock subclassing.
* The Doctor from ''VideoGame/AssassinsCreedBrotherhood'' is ExactlyWhatItSaysOnTheTin. As the official description puts it:
--> "He has assassinated more patients than he has saved, poisoned more targets than he has cured. [[WhiteMaskOfDoom No one has ever seen the real face of the Doctor…]] and he uses his deadly Syringe to make sure it stays that way."
** Pretty much every game of Assassins Creed Multiplayer has at least one DeadlyDoctor.
* ''VideoGame/LeagueOfLegends'' has three of these as optional skins for the ninjas: Nurse Akali, Surgeon Shen, and Kennen M.D.
** [[MadDoctor Dr. Mundo]] [[InvertedTrope inverts this]], as he's a [[HulkSpeak hulking brute]] with no immediate indication of being a doctor beyond his name. In spite of this, he's actually [[BunnyEarsLawyer quite brilliant]] in his line of work (that being a SerialKiller who experiments on his victims).
* ''VideoGame/DefenseOfTheAncients'' has Zharvakko, the WitchDoctor. While he's a very potent healer, his primary means of helping the team is using the same knowledge to conjure stunning projectiles and drastically amplify the damage dealt to enemies.
** [[LightIsNotGood Dazzle]], the Shadow Priest's descriptions say that there are very few spells his order of healers designed to harm - and even then not kill, but disable the foe. He can still unleash a lot of harm by [[ReversePolarity inverting their properties]].
* Dr. Litchi Faye-Ling in ''VideoGame/BlazBlue'' is another aversion. She's a clear doctor and helps in healing people, but she never brings her medical knowledge in combat, and usually fights with telekinesis, chi control and martial arts... nor did she specifically target some body parts for medical damage.
* ''VisualNovel/HatofulBoyfriend'' has Dr. Iwamine Shuu, the school doctor at St. [=PigeoNation's=] School. He is so deadly that [[spoiler: he may cut off your head, and possibly also study your insides ''most intimately'' once he's done with your pretty head.]]
* ''VideoGame/{{Skullgirls}}'' has Valentine, who fights with medical equipment such as bonesaws, syringes, IV stands, and more.
* You could consider Shadow [[spoiler:Naoto]] from ''VideoGame/{{Persona 4}}'' this. After all, [[spoiler:she was going to medically change Naoto's gender.]] That said, [[spoiler:she]]'s also a bit of an aversion. [[spoiler:She]] fights with the usual magic powers and technology, no real use of any sort of medical knowledge.
* The third boss of ''VideoGame/PersonaQShadowOfTheLabyrinth'' is the Kind Doctor, a giant deformed surgeon that [[ObliviouslyEvil believes]] he's performing life-saving surgery, not attacking the heroes. He's backed up by two nurses that respectively buff his offenses and defenses. [[spoiler:He is later revealed to be a manifestation of a deceased character's memory of the doctor who presided over the surgery in which they died.]]
* ''VideoGame/KeithCourageInAlphaZones'' has the enemy Dr. Sting, who flies through the air and throws syringes.
* Doc Mercy in ''VideoGame/{{Borderlands 2}}'' is a twisted, psychotic bandit doctor. His powerful laser gun doesn't follow a medical motif, but he uses a hospital sign as a shield and throws grenades that hurt others while healing him. Somehow, unlike his good guy rival Dr. Zed, he actually has both a medical degree and a medical license.
* [[VideoGameCrueltyPotential Very easy]] to be one of these in the surgery simulator ''VideoGame/LifeAndDeath''.
* Evil doctors are among the enemy types in ''VideoGame/SwordOfTheStars: The Pit''.
* Medic's Resonators in ''VideoGame/WildStar'' are useful for reconstructing and regenerating tissue and bone. They can also be super-charged to emit unsafe levels of radiation that can liquefy said tissue and bone. As Ish'mael the Bloodied said,
--> I used to scream "Medic!" with hope rather than terror. I may be a pirate but in some way I feel like I've lost my innocence.
* ''VideoGame/BravelyDefault'' shows us a magical version of this: the first White Mage you fight (and steal the powers from) is a torture specialist who uses her healing powers to keep her torture victims alive long past the point where they would have died normally.
* One psychopath in ''VideoGame/DeadRising3'' is a doctor who uses the zombie outbreaks as a way to harvest organs for a huge markup on the black market. Nick spends most of the fight drugged up from his injections and you have to turn them against him for the most damage. He also has one of the most disturbing deaths in the game.
* Traitor doctors in VideoGame/SpaceStation13 can be this. They have access to all sorts of chemicals that can be used on their victims, preform "surgery" on them, unleash a deadly virus, or just leave them to die and lose the body.
* Healers in ''VideoGame/MakaiKingdom'' are usually {{Squishy Wizard}}s who can't fight, since the stats are against them and they have to put all their points in Resilience to be competent at healing. However, the Syringe is both a HealingShiv and a potent weapon which employs your Res stat to determine effect. Once your healer gets her hands on this weapon, they can quickly move from a back-row redundancy to a competent (if not top-tier) damage dealer. And they still can do healing.
* Dr. Maddiman from ''VideoGame/YokaiWatch''. He was a hospital director that experimented on his patients when he was alive and now, as a yo-kai, uses his abandoned hospital as a front to steal hearts from unsuspecting victims. In his boss battle, he wields surgical scalpels in his left hand as makeshift claws, throws bottles of medicine to poison your entire team, and uses an IV drip attached to his exposed heart to heal himself.
** The third game in the series introduces Prof. Zero (known as Dr. E. Raser in western Wibble Wobble) and his PaletteSwap Dr. Kagemura [[spoiler:who was the son of Dr. Maddiman according to a sidequest]]. Both Yo-kai have a skill (though it's more evident in the latter, called Evil Medicine) which decreases the HP of their opponents gradually, and their Soultimates sprays poison on the opponents' field to cripple them when they move there.
* ''VideoGame/KirbyPlanetRobobot'' introduces the Doctor ability for Kirby, which gives him the ability to throw large vitamins at his enemies, along with attacking/shielding with a giant clipboard and brewing randomized elemental potions he can unleash on the enemy.
* ''VideoGame/DeadByDaylight'' has not one, but two of these.
** First is The Nurse. Once an impoverished young widow who took up a job at an asylum to make ends meet, she spent 20 years being physically and verbally abused before her mind eventually snapped, and she committed a mass slaughter of patients and staff. Now she exists in a nightmare dreamscape, spending all eternity slaughtering and sacrificing unfortunate victims for the Entity.
** Then there's the aptly named killer The Doctor. Unlike The Nurse, Herman Carter was one of these before he became a servant of the Entity. A psychopath working for an off-board CIA mind control program. People would beg and plead to not be sent to his office.
* Among the cast of twisted enemies in ''VideoGame/CarnEvil'' are deranged MonsterClown doctors (named "Dr. Klot") who attack with surgical saws, drills, and syringes. They appear during the final level, in which the BigBad, Professor Ludwig von Tökkentäkker, instructs them to extract the player's brain and put it into the Great Ape, a gorilla with guns for hands. Dr. Klot's voice clips can be found [[https://www.youtube.com/watch?v=wh7OGKJtiCI&feature=youtu.be here.]]
--->'''Dr. Klot''': "Your brain...in a giant ape! I'M A GENIUS!"
* Another aversion is Mercy/Dr. Angela Ziegler from ''VideoGame/{{Overwatch}}''. She specializes in healing or resurrecting her teammates and she is capable of combat... but not using medical expertise, but instead a normal handgun. Though headshots still apply, so she can still administer some 'skull cracking'.
* Using her syringe-arm and medical expertise of various diseases in battle, Beatrix from ''VideoGame/{{Battleborn}}'' is quite the badass of a deadly doctor.
* ''VideoGame/{{Tenchu}} 3: Wrath of Heaven'' introduced a new character named Tesshu who operated as a doctor by day and vigilante assassin for hire by night, making extensive use of his medical knowledge to make him a more effective killer.

[[folder:Web Animation]]
* Basically the defining character trait of Dr. Bob from ''WebAnimation/KlayWorld''.

[[folder:Web Comics]]
* In ''Webcomic/TheAdventuresOfDrMcNinja'', Dr. [=McNinja=], who fights in medical garb (but does so with standard ninja weapons). Played straight only once, when he had to defend himself with nothing but his stethoscope. It's broadly hinted that, while he is strong and stealthy because he's a ninja, what really makes him dangerous is his intimate knowledge of human anatomy.
--> '''Dr. [=McNinja=]:''' ''"Good evening. My name is Dr. [=McNinja=]. [[PreAssKickingOneLiner And I am going to be your phlebotomist tonight.]]"''
* Dr. Zexion of ''Webcomic/AnsemRetort''. Granted he doesn't fight with a medical motif, but he is a heartless killer, so he counts.
** He may not ''fight'' with a medical motif, but he certainly ''kills'' (and injures, and maims, and mutates) with one. Case in point: Riku's liver. Firecracker. Surgical implantation.
* ''Webcomic/{{Chainsawsuit}}'': Dr. Murder murders people. 'Nuff said.
* ''Webcomic/{{Archipelago}}'' gives us Captain Snow, who once apparently practiced as a doctor. Morally questionable procedures cost him his license, and now, he uses his anatomical knowledge primarily for torture.
* ''Webcomic/TheLawOfPurple'' has Doctor Dross, a possibly sociopathic doctor with a Hitlerstache.

[[folder:Web Original]]
* Atrocity from ''Brennus'' her specialty is medical equipment.
* Dr. Insano of ''WebVideo/TheSpoonyExperiment'' has a MorallyAmbiguousDoctorate, but his (unseen) nurse and tendency to carry around a stethoscope might put him in this category.
* ''Wiki/SCPFoundation'': [[http://www.scp-wiki.net/scp-049 SCP-049]], "The PlagueDoctor", believes that he's "curing" the Plague by killing people and turning them into zombies, unwilling to entertain any notion that the disease has not been a threat for a long time. At least, the Foundation ''assumes'' he's talking about the Plague...
* Doctor Locklear in the Doctor Locklear series. He uses his surgical knowledge to torture and then kill people accused of crimes who were released or ruled not guilty. He also used it to kill the night nurse checking on him in Good Doctor Locklear.
* Bonesaw from ''Worm'' is an expert in biology and surgery. She uses her talents to great avail, granting her fellow super villians subdermal armor, making controllable zombies from dead heros, and [[spoiler:turning Grue into a room's worth of pure, agonized, nerve cells.]]

[[folder:Real Life]]
* Dr. Solomon is a dentist who earned The Medal of Honor for saving wounded soldiers. He was treating the wounded when a Japanese soldier bayoneted a wounded soldier. He shot him dead when two more showed up and he killed them. Four more came under the tent while he was distracted. Like a badass he kicked a knife out of ones hand, shot another and stabbed a third. Captain Solomon [[UseYourHead Head-butted the last]] and a wounded soldier shot him. He told the wounded to escape as he picked up a rifle killed four that where on machine guns, he got onto the machine gun and killed 98 people. He was found dead with many bullets in him. He probably got shot multiple times [[DefianttotheEnd but continued to fight.]] He didn't get the Medal of Honor for nothing.
* John Henry "Doc" Holliday had a Doctorate in Dentistry, earned at the age of 21 in the year 1872, and later became a legendary gunslinger and friend of Wyatt Earp.