History ChekhovsGun / LiveACtionTV

*** Visible in Barton's office is a wireframe humanoid statue in a glass case. When the Doctor encounters the "Silver Lady" again in 1834, she realizes it's important: [[spoiler:it's a device built by the Master to make it easier for the Kasaavin to enter the main universe, and the Doctor takes an opportunity later to program it with some code that will sabotage the grand plan.]]

* ''{{Series/Dollhouse}}'':
** In season 1 Ms.Lonely-Hearts who is joked about much early on eventually is revealed to be [[spoiler:Adelle.]]

* ''Series/TheMentalist'': In the third season, it takes on the form of a literal gun. Earlier in the season Jane is given a gift of a pistol. He has never owned a pistol and is not the kind to own one, but he holds it in his hand pensively. It's seen again once more briefly but is more or less forgotten about. [[spoiler:That is until the very end of the season finale, when he keeps it hidden in his suit pocket and actually kills Red John with it, finally fulfilling the objective he'd been obsessed with since the beginning of the show.]]

--->'''Buffy:''' You had sex with Giles? On the hood of a cop car? TWICE!?

*** The first episode introduces the Osterhagen key, established as a rather obvious Chekhov's Gun; the finale also introduced ''two'' further devices with the potential to end Davros' plans, and characters threaten to use all three at the same time. The whole thing is subverted when the Daleks casually separate the characters from their respective doomsday devices. All seems lost until the ''real'' Chekhov's Gun goes off when Donna's Time Lord consciousness is awakened from the human-Time Lord metacrisis.

** In [[Recap/DoctorWhoS31E5FleshAndStone "Flesh and Stone"]], the Doctor walks away from Amy, earlier having lost his coat to a Weeping Angel. He then returns, warning Amy to keep her eyes closed, lest she allow the Angels access to the vision centres of her mind, and also telling her to remember what she told him when she was seven. The latter is shot entirely in close-up, and the Doctor's jacket-clad shoulder is only occasionally glimpsed (did Continuity miss something?). In fact, the Doctor who talks to Amy in the forest [[spoiler:is actually the Doctor from the future, rewinding his timeline due to the events of]] [[Recap/DoctorWhoS31E12ThePandoricaOpens "The Pandorica Opens"]]/[[Recap/DoctorWhoS31E13TheBigBang "The Big Bang"]]. [[spoiler:The thing he told her when she was seven was a story about him and the TARDIS, meant to make her remember him at her wedding after he was erased, so he could be brought back into existence.]]

*** The Master's ring from "Last of the Time Lords", last seen being picked up by a mysterious woman. Creator/RussellTDavies originally planted this Gun with the intent of letting a future producer fire it, only to do so himself.

* ''{{Series/Dollhouse}}'': In Season 2, [[spoiler:many of the imprints from Season 1 begin reappearing as necessary to the plot.]]

* ''Series/TheTwilightZone1959'': The episode "Hocus-Pocus and Frisby". Near the beginning of the episode Frisby is playing his harmonica, and someone asks him to stop because of its poor sound. Near the end of the episode he plays it while he's being held prisoner by aliens, and the music acts as a "[[BrownNote death sound]]" on them.

** [[Recap/DoctorWhoS30E13JourneysEnd "Journey's End"]]:
*** The [[Recap/DoctorWhoS30E12TheStolenEarth previous episode]] introduced the Osterhagen key, established as a rather obvious Chekhov's Gun; the finale also introduced ''two'' further devices with the potential to end Davros' plans, and characters threaten to use all three at the same time. The whole thing is subverted when the Daleks casually separate the characters from their respective doomsday devices. All seems lost until the ''real'' Chekhov's Gun goes off when Donna's Time Lord consciousness is awakened from the human-Time Lord metacrisis.

* ''Series/{{Zoey 101}}'':

*** While examining the alien pod, the Doctor identifies a recall circuit intended to send the occupant home. At the climax, she threatens to destroy it in a HostageForMacguffin situation.

** River Song's lipstick offers a slight variation on this trope. Initially, her hallucinogenic lipstick is used by her to escape from jail in "The Pandorica Opens", it returns in [[Recap/DoctorWhoS32E8LetsKillHitler "Let's Kill Hitler"]], [[spoiler:this time as poison from the Judas Tree, which she has worn as part of her plan to kill the Doctor.]]
** The Teselecta from "Let's Kill Hitler" is revealed in [[Recap/DoctorWhoS32E13TheWeddingOfRiverSong "The Wedding of River Song"]] [[spoiler:to have taken the place of the Doctor at Lake Silencio, allowing him to survive.]]

* ''Series/{{Lost}}'': Subverts this concept by introducing roughly two million potential Chekhov's Guns and then only making use of about one million of them. [[TropesThatWillNeverHappen You Fail The Law Of Conservation Of Detail Forever]].

** [[Recap/DoctorWhoS21E1WarriorsOfTheDeep "Warriors of the Deep"]] features intelligent reptiles as the MonsterOfTheWeek. Early in the story, a character identifies bottles of '[[AppliedPhlebotinum hexachromite gas]]' as lethal to all reptile life, making the climax rather predictable.

** [[Recap/DoctorWhoS30E3PlanetOfTheOod "Planet of the Ood"]]: The villain, Mr Halpen, is constantly drinking hair tonic given to him by an Ood slave. Later, we find out that the Ood have been feeding him a biological compound... which turns him into one of his own slaves.

** The Chameleon Arch introduced in [[Recap/DoctorWhoS29E8HumanNature "Human Nature"]] shows up again in [[Recap/DoctorWhoS29E11Utopia "Utopia"]], [[spoiler:this time being used by the Doctor's old ArchEnemy the Master, who used it to hide as a human after surviving the Time War]].

** The one exception to this otherwise hard and fast rule occurs in the episode ''Return of the Cybernauts'', where fashion sense (Emma was going to a formal party) and the plot (she will later attack Steed after being mind controlled) could not be meshed, resulting in an oddly surreal scene where the villain of the piece pulls off her skirt after mind-zapping her so that she can perform the subsequent, oddly stilted, fight scene.

** Throughout the first and second seasons, various uniformed marines are seen throughout the town, and there are passing references made to "Camp Genoa." In Season 3, Camp Genoa is revealed to be a USMC base in Banshee County, with [[spoiler:the money stored there and the corrupt commander in charge]] becoming the main focus of the season.

* ''Series/{{Elementary}}'': In the opening of "The Rat Race", Watson complains that she can't read Holmes' texts because he uses too many abbreviations. [[spoiler: After the killer of the week kidnaps Holmes, she sends a text from his phone so Watson wouldn't worry. However, Watson realizes it wasn't from Holmes because [[OutOfCharacterAlert it didn't read "like a teenager on a sugar high.]]"]]

** Eureka did this a LOT. Usually within the first fifteen minutes of a given episode, two experiments would be shown and explained. One of them causes this week's catastrophe, the other (using Carter's inimitable stupid logic) is the solution.

** Jorah Mormont explains to Rakharo that a Dothraki ''arakh'' won't pierce plate armour. Qotho discovers the fatal truth of this in "Baelor."

* ''Series/{{JAG}}'': In the episode "Brig Break", Lt. Kate Pike and Lt. Meg Austin have a minor disagreement whether the proper title of the visitor's registration form for the brig is -77401 or -77501. At the climax, gunnery sergeant in charge of the brig has activated a nuclear weapon and it can only be deactivated by entering a five digit code. Since the Gunny had perversely tormented Meg by telling her the 5-digit code he picked "has a seven in it", Meg, Harm and Kate desperately try to choose a string of numbers with a seven in it that Gunny might have used on a regular basis.

* ''Series/LawandOrderCriminalIntent'': Near the beginning of one episode, Bobby Goren "buys" a brick from a homeless man (in order to take it before said homeless man hurts someone). Halfway through the episode, he uses the same brick [[spoiler:to destroy the window of a car shop belonging to a small-town judge in order to get himself arrested so he can go undercover in the local prison.]]

* ''Series/MacGyver'': Angus [=MacGyver=].

* ''Mistborn Chronicles'': Vin's earring.

** There are also instances where Chekov's guns are shown where Monk isn't the one who noticed it. A notable example is in the episode ''Mr. Monk and the Captain's Wife'': During the scene where Captain Stottlemeyer is going [[BerserkButton berserk]] with rage in trying to find the person who shot the tow truck driver and thus hospitalized and nearly killed his wife at the police department, a detective mentions a bank job in which a 22-year old clerk was killed, that Stottlemeyer dismisses. Turns out, that culprit hid the gun he used in his car, which was being repossessed by the tow truck driver on the morning of the shooting.
** In ''Mr. Monk and the Big Reward,'' Monk makes a point of reminding the police station's cleaning lady to clean ''under the tables.'' As it turns out, [[spoiler:the lost million-dollar diamond is hidden under a table in an interrogation room with a wad of gum, and the cleaning lady finds the diamond by accident after Monk has figured out where it is.]]
** In "Mr. Monk Goes to a Rock Concert," they spend plenty of time showing Monk being hit by a blue beach ball. Which turns out to have the incriminating evidence.
** In "Mr. Monk and the Bully," Marilyn Brody mentioning to Monk and Natalie that she was adopted and had an aunt in Texas. The word "aunt" is important, since she pronounces it differently ("awnt" vs. "ant") later, allowing Monk to deduce that she has a twin.
** In "Mr. Monk and the Leper," they do the job of showing you a security panel in the house Monk and Natalie are paid to sneak into, which clearly says is from a security company founded in 2003. Since the person who is paying Monk has been presumed dead for seven years, after Monk overhears Julie reading off a ketchup bottle from a producer that has been making it since 1840, Monk realizes he's been a DetectivePatsy.
* ''Series/MurderSheWrote'': Apparently the main employer of Cabot Cove is a factory that makes Chekhov's Guns.

* ''Series/{{NCIS}}'': In one episode, Tony steal's [=McGee=]'s apple, munches on it, and tosses the core away in Abby's trash bin. Just yet another example of Tony treating [=McGee=] like the ButtMonkey, right? Yes, except two episodes later we find out that [[spoiler:Chip stole the discarded apple in order to get a copy of Tony's teeth marks, and used them to frame Tony for murder]].

* ''Series/PowerRangersTimeForce'': The rangers came from the year 3000 which was later revealed to be a razed earth with cities few and very, very far between. Fast forward ''eight'' years later to ''Series/PowerRangersRPM'' where we are shown as to how it happens.

** It first seems a slightly eccentric gift from Harvey (12:36 is the time Harvey and Sabrina first spoke back in the "Pilot" episode). However, when Libby steals Mr. Pool's engagement ring and attempts to frame Sabrina for the crime, the bracelet turns out to be key to establishing an alibi for Sabrina's.

** ''Atlantis''' parent series ''Series/StargateSG1'' is an example of ChekhovsArmory, but its episode "Emancipation" features a literal ChekhovsGun, namely O'Neill's Beretta M9 sidearm. Early in the episode he fires it into the air to frighten off some wild dogs, then to startle some [[SpaceRomans Space Mongols]]. [[spoiler:He later trades it to a chieftain named Turghan in exchange for him letting Carter go.]]

* ''Series/UnnaturalHistory'': Chekhov's [[spoiler:Muffins]].

** Meredith's stash of blood in the Season 3 Finale

* ''Series/{{Zoey 101}}'': In one episode, Zoey's key (which she always wears on a chain around her neck) turns out to be way useful - it is used to stop the reactors in the school's new electric generators from blowing up the entire school. This is a more extreme example, though, as it was something that she did in one of the first few episodes, and this episode wasn't until season 3.

* ''Series/AgathaRaisin'': In "Agatha Raisin and the Fairies of Fryfam", Gemma tells Agatha that a good cleaner always carries a squirt bottle of 3-in1 disinfectant to ward of the amorous advances of any male householders. At the end of the story, Agatha stops the killer by spraying them in the face with 3-in-1 disinfectant.