Oliver (on choosing to kill the Count): Felicity... he had you and he was gonna hurt you. There was no choice to make.
- After five or so years of semi-righteous murder left and right, Oliver Queen attempts to do his vigilante work with less collateral damage (barring that of property, of course) after Tommy's death. However, this trope is danced around, as he instinctively puts three arrows in Count Vertigo when the latter grinningly threatens Felicity. And all this mere weeks after the vow is made, too. His resolve is nowhere near as strong as that of his counterparts.
- Since then, he mostly keeps to the rule, only killing when absolutely necessary. What causes him to actually backslide is Laurel's death in Season Four. Not only does he kill her murderer Damien Darkh, he almost discards the rule entirely, only going back to his previous provision of killing when necessary after a talk with Thea and the Trauma Conga Line that is the latter half of Season Five.
- Buck Rogers in the 25th Century: Buck gets into a lot of fights but never kills anyone directly. He never shoots anyone to death; this is easy to pull off since the rayguns are usually set on stun. The only time that a villan died due to Buck shooting him was Happy Birthday Buck. However, it was still a stun beam and the villain died due to falling on his hand and turning himself to stone with his own Right Hand of Doom. Space Battles are a different story, however. It can be assumed that pilots are killed when their ship is destroyed. But in The Plot to Kill a City, this was shown to not always be the case. Also, ship to ship battle is often considered an impersonal form of killing since the two combatants don't see each other face to face, although in Planet of the Slave Girls, Galen, The Dragon to Jack Palance's villan charcter clearly did not survive his space duel with Buck. Buck directly arranged for the Vorvon to be destroyed in Space Vampire, but being a vampire, the Vorvon probably does not count.
- Buffy the Vampire Slayer: Slayers are definitely not supposed to kill humans (even villainous humans). Vampires and other assorted demons are fair game. Although there were a number of Karmic Deaths for the human enemies. There was also that time she had to kill about ten of the Knights of Byzantium to defend herself and her sister, one by throwing an axe into his chest at pointblank range.
- After Faith accidentally kills a human with a wooden stake while still on a massive adrenaline rush after a fight, seconds after Buffy tries to warn her Giles actually tells Buffy that due to the high-stress nature of the Slayer's job, the Watcher's Council expects one or two accidents and has ways of dealing with them. This doesn't stop the angst on the part of the accidental murderer, though. An episode soon after shows Buffy stopping just short of the killing blow to a vampire after Willow cries out, in exact parallel to the situation with Faith, showing that Faith could have avoided killing the deputy mayor if she had a clearer head. Shortly afterwards, Faith's poisoning of Angel drove Buffy to nearly kill her so that her blood could be used as an antidote. Thankfully, Faith was only put in a coma and Buffy snapped out of killer mode, though actually entering it in the first place haunts her for a good long while.
- Mentioned in one episode when Ethan Rayne tells Buffy she can't do anything to him since he's human, only for The Initiative to arrest him.
- The same rule also generally applied to Angel, though he had quite a few "exceptions" to it throughout the series' course. Humans were excluded if they had supernatural powers. Even then there was the episode "Conviction" where Angel killed a special ops soldier who was technically his employee by kicking him causing him to shoot himself in the head, just to make a point that the soldier's way of doing things wasn't going to be tolerated anymore under Angel's management.
- Chuck: Chuck could never bring himself to kill an enemy no matter how much they deserve it, which is the reason why he Doesn't Like Guns and would rather use tranqguns instead. The closest he came to actually killing anyone was shooting Shaw and dropping him into the river to save Sarah (though he survived) and grabbing him by the throat in their final confrontation.
- Heroes: Matt Parkman had ample justification to kill Emil Danko, who is heading a program started by Nathan Petrelli to round up persons with special abilities. First, Danko's operatives shoot Matt's girlfriend Daphne. Then when Danko takes control of the operation he removes the still-living Daphne from the medical facility. Consequently, Daphne develops sepsis, leading to her death. Parkman seeks to get even by taking away the most important person in Danko's life, a call girl named Elena who knows Danko as "Jakob Pradasa". He telepathically forces Danko to divulge his true identity, to admit what he does (hunting and abducting people), and to confess that he let Daphne die. Parkman then points his gun at Elena, but cannot bring himself to shoot her.
- Supernatural: Hunters are supposed to kill evil monsters and protect humans, but at least in Season 1, Sam and Dean refused to kill humans (though Dean followed this rule mostly to appease Sam). However, when up against truly monstrous humans, Sam and Dean have had to kill. As Dean said "Demons I get, humans is just plain sick." This rule pretty much ceases to exist after the first season, but they still insist on trying to save as many people as they can at all times. Strangely, this doesn't apply to people who are possessed; while initially they would only kill demons (and their vessels by extension) if they really had to, they gradually become more OK with it and even sometimes force a demon into a vessel in order to kill both. By Season 10 (if not earlier), both of them have given up on avoiding killing at all, even of innocents, and are solely concerned with saving each other. They've returned to their Season 1 attitude in Season 11 due to a Heel Realization.
- Terminator: The Sarah Connor Chronicles starts off with John and Sarah like this. Derek and Cameron, not so much. Sarah frequently orders either or both of them not to kill (they tend to take it under advisement). The first season features Sarah's reluctance to kill a man she believes will one day create Skynet, and is shown dwelling on it. A common theme throughout the series is the importance of human life. However, Sarah ends up being forced to kill a man midway through season two and John even earlier.
- Doctor Who: This is the Doctor's apparent modus operandi. Give him points for effort, but it doesn't usually work.
- Of course, depending on just how far an enemy pushes him, he might make them genuinely wish he just killed them.
- Heavily subverted in the seventh season episode "Dinosaurs on a Spaceship". Sure, that guy had committed genocide on an entire shipload of refugees and tried to enslave queen Nefertiti of Egypt. Being used as a missile decoy was the least he deserved, but coming from the Doctor that was cold.
- Completely subverted by the creation of the War Doctor, whose entire purpose was to bring about the swift conclusion of the Time War in the most efficient manner possible, regardless of how many deaths that caused. He outright asks to be made into a Warrior before he starts that regeneration.
- In Smallville, Clark Kent refuses to kill enemies, but he does not consider Karmic Death or accidental death to be murder. The one time he attacked an opponent (Titan) with the intent to kill, he was haunted after he did the deed. Chloe also stresses this often, sometimes to meteor freaks who aren't bad at heart. Oliver on the other hand... It leads to clashes between him and both Clark and Chloe. He often tries to get them to do what he does.
- Chloe: This is murder.Oliver: This is justice.
- Clark also doesn't hesitate to kill Brainiac, justifying it with the lame technicality that Brainiac is a robot.
- In another episode, Chloe admonishes Clark that he should not hesitate to let her die if that's what it takes to save the world.
- In the 1998 miniseries Merlin (the one with Sam Neil), this is the limitation of the magic of The Fair Folk, that it cannot be used to kill, according to the novelization.
- The Leviathans of Dark Shadows have this as a rule. Not due to any sort of morality, but rather because anyone they kill will become a super-powered ghost, capable of hindering their plans even further. At least that's how it's supposed to work, but due to Real Life Writes the Plot issues the matter was rather derailed.
- Michael from Prison Break fluctuates between this and Technical Pacifist.
- In Have Gun Will Travel, Paladin will avoid killing if possible, and more than one episode ends without anyone dying. When it becomes necessary, however, he won't hesitate.
- Tracker Cole does not kill; he just incapicates the human long enough to withdraw the life force from the body. Justified, because Cirronians are a peaceful species by nature, and abhor violence (yes, even the criminals-most are in prison for nonviolent crimes).
- Gabrielle, of Xena: Warrior Princess.
- In the pilot episode of The Incredible Hulk, David Banner's research partner assures him that the Hulk will not kill, "because David Banner wouldn't kill." Nevertheless, David spends the series worrying that the Hulk will one day cross the line. (He doesn't, but only because so many of the bad guys are Made of Iron.)
- Shepherd Derrial Book from Firefly follows the Ten Commandments to the letter, including the Trope Namer. However, he rather dryly notes in "War Stories" that the Bible is "somewhat fuzzier on the subject of kneecaps." In Serenity, after shooting down the Alliance gunship that just mortally wounded him and burned his town to the ground, he comments that it was "not very Christian of me." This is explained somewhat in the comic books: He spent the Great Offscreen War doing black ops, including assassinations, and is now The Atoner.
- The Shaolin philosophy from Kung Fu has this as one of it's core tenets. "Avoid rather than check. Check rather than hurt. Hurt rather than maim. Maim rather than kill. For all life is precious nor can any be replaced."
- Played completely straight with the title character of MacGyver, due to a childhood incident in which he accidentally caused the death of one of his friends with a handgun they'd stolen to play with. Occasionally comes across a strong temptation to use one, but always finds another way. In one of the TV movies, the terrorist group he's trying to infiltrate orders him to execute one of their defeated members: he reacts by emptying the clip right over the terrorist leader's head for effect, shouting that only a stupid leader would waste his men's lives like that, and pretending to walk out by saying he was looking for "professionals, not suicidal punks." It works. Furthermore, it's so deeply ingrained in him that even on the couple occasions he loses his memory and finds himself pointing a gun at somebody, he can't make himself pull the trigger.
- The only time we've seen him in a nearly murderous rage was right after catching a racist who'd had one of his best friends lynched, whom he caught in the middle of printing his white power pamphlets, and who wasn't so much bragging about it as shrugging the whole thing off (oh, he also tries to shoot him). A cop calls him back to his senses just before he can deliver a no-holds-barred and possibly fatal beating.
- In an oft-cited case of Early Installment Weirdness, the pilot episode does feature Mac picking up a machine gun and returning fire against Soviet troops. This might not be an aversion, though - he only fires once or twice and we don't see anyone being hit, so it's easy to write off as simple covering fire to give himself time to escape.
- Less cut and dried with the main characters of The A-Team. They never kill anybody onscreen, but it's not clear how much of this is due to their own methods, and how much of it is just the television show trying to remain family friendly (especially since they get into gunfights on a regular basis and we often see people surviving things that would clearly be fatal in real life). No one in the A-Team has a strongly voiced opinion against killing and even less against guns - as Vietnam veterans and a former Special Forces unit, it's a foregone conclusion that they have killed people before. At the same time, they routinely pass up opportunities to kill enemies that they have at gunpoint, and much prefer to simply beat the tar out of the villains and leave them tied up for Colonel Decker to put in jail.
- In The Flash (2014), Leonard Snart/Captain Cold is a petty thief turned supervillain who doesn't kill if he can help it, but will if forced to or crossed. This is mostly out of pragmatism rather than any kind of morality, as he finds the consequences of murder more trouble than they're usually worth. After Flash challenges him to continue his supervillain career without killing anyone, he accepts, seeing it as a true test of his skills.
- Person of Interest:
- Ex-CIA assassin John Reese tries to avoid killing people (his fondness for Knee Capping is a Running Gag) though he has done so on occasion, often as a Karmic Death. When his Distaff Counterpart Sameen Shaw joins Team Machine in Season 3, she visibly chafes at this restriction, feeling no embarrassment whatsoever about being a sociopathic Blood Knight. She does still follow it, though.Shaw: [after shooting a mook] In the arm, through a brick wall, in the dark. You're welcome.
[mook stumbles off a ledge and falls to his death]
- Reese actually lampshades this in episode S1E3 Mission Creep: though soldiers in general specifically trained to kill in combat, significantly fewer are capable of killing in cold blood, let alone up-close and personal.Killing in battle, in combat, is one thing. Killing someone up close, someone who can't fight back, that takes a different sort of killer.
- The Machine forces the amoral hacker Root into this restriction as well in order to utilize her Machine Worship for good causes. It actually ends up basically reprogramming the former mercenary into one of the strongest forces for good in the series. The Machine understands that sometimes its assets need to kill people, but never orders it itself. This actually causes the bad guys to win a couple key battles.
- Ex-CIA assassin John Reese tries to avoid killing people (his fondness for Knee Capping is a Running Gag) though he has done so on occasion, often as a Karmic Death. When his Distaff Counterpart Sameen Shaw joins Team Machine in Season 3, she visibly chafes at this restriction, feeling no embarrassment whatsoever about being a sociopathic Blood Knight. She does still follow it, though.
- Daredevil (2015) makes it a hard rule not to kill, and is one of the only heroes in the Marvel Cinematic Universe to do so (The Hulk is a special case as Bruce Banner tries hard not to kill anyone but ultimately has no control over the Hulk's actions; the MCU version of Spider-Man has yet to be seen using deadly force and his views on the subject are as yet unknown). This mostly comes from the fact that he's a devout Catholic and knows he's toeing the line of morality already by administering brutal beatings to criminals. This rule is challenged in the second season when he's contrasted with remorseless killers Elektra and The Punisher; Daredevil's appalled at how they kill their enemies, but at the same time his insistence at keeping everyone alive sometimes puts him and his allies at risk.
- Supergirl: Supergirl follows the same general "Thou Shalt Not Kill" policy as her cousin, which has led to a few baddies escaping. That does not mean she has not had to destroy a few alien baddies from time to time, and she also destroys the Red Tornado in a fit of anger, not realizing that he'd become sentient a few moments before. The rule is decidedly not followed by her DEO colleagues, including her sister, Alex, who is a trained killer and uses such skills on more than one occasion. The Guardian, although he delivers Daredevil-style beatdowns on bad guys, also adheres to Supergirl's no-killing rule.
- Iron Fist (2017): Claire believes this, though Colleen disagrees, and they argue about it.
- Wonder Woman: Wonder Woman declares in the pilot, "The New Original Wonder Woman", "Where I'm from we try never to hurt people". Aside from a couple of war related incidents and an encounter with Hitler in "Anschluss 77", Wonder Woman's opponents generally let off very lightly especially considering what she is capable of. She'd often let the hired thugs simply go since they're no threat.
- The Outer Limits (1995): In "Aftelife", Stiles declines to kill the commandos sent after him even to defend his own life.
- Hercules: The Legendary Journeys: downplayed with both leads. Hercules and Iolaus will kill in self-defense or to save others, but only as a last resort. Iolaus makes a point of saying in "Stranger In A Strange World" that killing in combat is a lot different than simply knifing a villain in the back (though this particular villain is the Sovereign, Herc's Mirror Universe Evil Twin, so Iolaus ultimately feels he has no choice but to try). "Doomsday" also explores this trope when an old enemy of Herc's (Nikolos) returns to wreak havoc. It's pointed out to Hercules that he could've killed Nikolos at the Battle of Plataea and prevented the current threat, but Herc counters that Nikolos had been completely defeated at the time and that he is not an executioner.
Thou Shalt Not Kill / Live-Action TV