At its simplest form, a character reveals himself to be an undercover police officer, FBI agent, what have you. Often, he's acting as a ReverseMole, trying to get enough evidence on the villain to arrest him for ArsonMurderAndJaywalking. It's entirely possible that we, the viewers, won't find out until the rest of the characters do as well. Depending on what side of the SlidingScaleOfIdealismVersusCynicism, this may or may not end badly for the cop.

Closely related to TheInfiltration, which involves a law enforcement officer pretending to be a criminal in order to join/infiltrate the bad guys' organization.


[[folder: Advertising ]]

* Happens in "[[ Crunchie Train Robbery]]". When the outlaws come out carrying the box of Crunchies, a respectable looking matron leaps up and rips open "her" blouse to reveal a sheriff's star.


[[folder: Anime And Manga ]]

* One Sinnoh-era ''Anime/{{Pokemon}}'' episode had one of these with an undercover Officer Jenny. There was a possible vague hint with Brock going into his usual routine when the group met her, but it was still hidden fairly well.


[[folder: Comic Books ]]

* Done twice in "A Night at the Rose Petal" in ''ComicBook/TheMazeAgency Annual'' #1. [[spoiler:Once with Jen disguised as an old drunk, and once with Lt. Bliss disguised as a hooker.]]
* Happens twice in the ''ComicBook/ChickTracts''.
** In "Bad Bob", Bob and his cousin deal drugs, and find out their buyer is a cop when he reads them their rights.
** In "Trust Me", the kid, to fund his drug habit, sells drugs to an undercover cop with a briefcase full of money, resulting in the cop pulling out a pistol and a badge, which is less surprising than most examples of the trope because he gets down on his knees and says "[[TitleDrop Trust]] [[SchmuckBait me]]!".
* ''ComicBook/TwoThousandAD'':
** Happens in ''ComicBook/TheSimpingDetective'''s pilot strip ''Gumshoe''. Jack is working Angeltown as a PrivateInvestigator and is coerced into a back alley by a client, where he is accosted by ninjas. When he takes them down, the client gets the drop on him. He reveals that it was a feint and pulls out his badge, as his backup arrives.
** Subverted in a ''ComicBook/JudgeDredd'' story when Dredd inspects a PenalColony in the Cursed Earth where standards under the new warden have dropped considerably and the prisoners have free rein. Their leader claims to be an undercover Judge in the warden's office, which Dredd "accepts" for the moment while he does a background check. He knew that Dredd would find out the truth anyway, he was just stalling for time.
* Happened in most "Sgt. Streetwise" photo-comic strips in ''ComicBook/NewEagle'', as disguises were Sgt. Wise's specialty. Sometimes the reader would know which character was Wise was the beginning, and at other times not till he revealed himself when he sprung into action.
* ''ComicBook/{{Copperhead}}'' gets a short play when Sheriff Bronson infiltrates the Bastion brothel, grabs her target, and immediately takes him hostage.


[[folder: Fan Fic ]]

* In the ''FanFic/AlvanAnTheChipmunks3TheSecondSqueakuel'', [[spoiler:Music/SnoopDogg]] turns out to be a member of the police.
* ''[[ Call Me Over to the Other Side]]'' by Kearlyn is a [[Film/PacificRim Pacific Rim]] AU in which Raleigh Becket joins the FBI to infiltrate Kaiju cults. Of course, the Kaiju-worshipping cultists don't trust him at first, and he's forced to take a bullet in order to win their trust. Thankfully, it's worth it, since he's able to [[spoiler: save the kidnapped pilot Chuck Hansen.]]


[[folder: Films -- Animated ]]

* [[spoiler: Roz]] in ''WesternAnimation/MonstersInc'' turns out to be an undercover agent of the CDA. And not just an undercover agent, [[spoiler:but the head of the whole freaking organization!!]]
* In ''WesternAnimation/TheChipmunkAdventure'', the mysterious [[spoiler: Jamal]], believed to be a rival criminal of Klaus and Claudia, turns out to be working for Interpol. Of course, we don't see him undercover- just working out of an office while addressing his thug-like subordinates. The siblings' butler Mario, however, is first shown telephoning intel, so [[spoiler: Jamal's]] also reveals him.


[[folder: Films -- Live-Action ]]

* ''Film/ReservoirDogs'': Mr. [[spoiler:Orange]], just after killing Mr. [[spoiler:Blonde]].
* In ''Film/TheFastAndTheFurious,'' Brian O'Conner reveals to Mia that he is a cop at the end of the movie. The viewer has known this all along but it allows some drama between O'Conner and the girl he has been sleeping with and [[spoiler:eventually persuades her to help him track down the truck thieves]].
* ''Film/RunningScared1986''. When detectives Hughes and Costanzo try to arrest Gonzales and end up caught in an ambush, two of Gonzales' men reveal themselves as undercover cops Montoya and Sigliano and save the {{heroes}}' lives. This is an EmbarrassingRescue from their point of view, [[UngratefulBastard and they even try to blame the agents for stuffing up their arrest]].
* In ''Film/BlackDog'', [[spoiler: Sonny]] reveals to Crews that he is an FBI agent after he is mortally wounded in a truck-jacking attempt.
* In the final ending of ''Film/{{Clue}}'', [[spoiler:Mr. Green]] reveals himself as an FBI agent, just after shooting [[spoiler:Wadsworth who is the real Mr. Boddy]]. In the first two endings, it is [[spoiler:Wadsworth]] who is revealed as an FBI agent after unmasking the mastermind behind the murders that have taken place. In all three endings, the evangelist who knocked at the door just before the summary of who killed whom is also revealed as an FBI agent.
* At the end of ''Film/TheSpanishPrisoner'', Joe is saved by [[spoiler: a pair of Japanese tourists]] who turn out to be undercover U.S. Marshals who have had Jimmy's con under observation since the start.
* In ''Film/TheWholeNineYards'' [[spoiler:the assassin the cheating wife hired to kill Oz was actually a cop recording their conversations. He wasn't outed until after being killed by Jimmy, scaring Oz's wife away]].
* In ''Film/{{Unknown 2006}}'', the protagonist is revealed to be a ReverseMole, an undercover cop infiltrating a criminal gang. The point is, he doesn't know of this for most of the plot because of temporal amnesia.
* ''Film/TheTakingOfPelhamOneTwoThree''. A plainclothes transit cop is believed to be one of the hostages, but no-one can find out who he is. 'He' might even be a woman, it's suggested. It turns out to be the hippie, who in a BrickJoke is [[DudeLooksLikeALady mistaken for a woman]] by Lt. Garber because of his long hair.
* In ''Film/BreakheartPass'', [[spoiler:Deakin]] reveals himself as a Secret Service agent. [[spoiler:Rev. Peabody]] is his partner. However, the partner has been murdered by the time this revelation is made.


[[folder: Literature ]]

* In Creator/RobertAHeinlein's ''Literature/MagicInc'' the heroes are helped by an UndercoverCopReveal when, essentially, fighting the literal forces of Hell. An FBI agent masquerading as a demon.
* ''Discworld/{{Maskerade}}'' is set up to look like Andre might be the villain until he reveals that he is actually an undercover cop.
* ''Literature/TrickyBusiness'', a rare non-humor book by Creator/DaveBarry (although it does have its moments), is about an illegal casino ship that is also a base for drug dealers, things go wrong, etc. On of the POV characters is a pretty young lady who works as a cocktail waitress, hates her job, and her mother always tells her to quit because it's so dangerous... Makes perfect sense, until the very last part of the book when it's revealed that "cocktail waitress" was just a disguise: she is actually a badass undercover cop, and now everything suddenly sounds a lot smarter.
* Creator/TimothyZahn's not-quite-''Franchise/StarWars'' SpaceOpera-Mystery-action book ''Literature/TheIcarusHunt''. To say more would be to spoil it, though if the reader is both paying attention and actively trying to put the pieces together, it's not ''that'' hard to figure it out ahead of time.
* In the Creator/TimDorsey novel ''Hammerhead Ranch Motel'', one room at the motel holds two different drug gangs who are secretly undercover cops each of whom is trying to bust the other gang. They only discover this when a third jurisdiction of police shows up and tries to bust both of them.
* At the very end of Creator/PatriciaCWrede's ''Literature/MairelonTheMagician'', [[spoiler:William Stuggs, Jasper Marston's apparently dim-witted henchman]], calmly reveals himself to be a Bow Street Runner. This is helpful, as it means he's witnessed the entire climax and has no uncertainty about who to arrest.
* Cyrus Hardman in ''Literature/MurderOnTheOrientExpress'' is a PinkertonDetective posing as a TravelingSalesman.
* Done in the very last word of Creator/MickeySpillane's ''Deep''.


[[folder: Live Action TV ]]

* ''Series/{{Angel}}'': Kate in her first appearance ("Lonely Hearts").
* Turned UpToEleven in a sketch in ''Series/DoNotAdjustYourSet''. The undercover cop reveals himself to be one to a gang, now that he's got enough evidence to convict them...[[FlockOfWolves and then all of them turn out to be undercover cops.]]
-->'''Jenkinson:''' Blimey...we're all coppers...\\
'''Johnsson:''' ...So what do we do now?\\
'''Leader:''' ...Jenkinson, can you blow up a safe?
* ''Series/BreakingBad'' : In the opening of one episode Badger, one of Jesse's friends and dealers in Walter's infant meth empire, gets arrested after being baited into selling an under cover cop meth by falling for the urban myth that undercover cops have to reveal themselves if asked about their secret directly.
* ''Series/FastLane'' episode "Mighty Blue". When officers Van and Deaq confront a criminal gang, one of them reveals herself as an undercover police officer to save them.
* This happened to Sawyer in the "flash-sideways" on ''Series/{{Lost}}'' - the scene deliberately echoed a season one flashback which showed him as a con man, only this time the mark called him on it, and he revealed that he was a cop.
* In the ''Series/DoctorWho'' story "[[Recap/DoctorWhoS14E5TheRobotsOfDeath The Robots of Death]]", one of the Sandminer's crewmembers is revealed to be an undercover agent -- and [[spoiler:so is one of the robot drones, which is actually a highly advanced robot disguised as the most primitive and stupid model in use on the Sandminer]].
* Occurs in the first episode of ''Series/RookieBlue'', even though he tries to keep his cover even after being arrested. Its finally blown when an old friend greets him heartily as he is about to be processed.
* Happens in the episode of ''Series/TheBill'' that re-introduced Frank Burnside. Burnside was undercover with a gang of soccer hooligans that are busted by Sun Hill. Burnside headbutts one of the arresting officers to maintain his cover.
* ''Series/HawaiiFive0:'' Sid in "Mala Ka Aina"; Kono in "Ma'eme'e".
* Liam in ''Series/TheChicagoCode''.
* In ''Series/{{Suburgatory}}'', a student that Tessa assumed to be gay actually was an undercover narcotics agent.
* One episode of ''Series/VeronicaMars'', "Weapons of Class Destruction", involved a suspected plot to bomb the school. One of the prime suspects turned out to be an undercover ATF agent[[note]] Invoking an in-universe version of DawsonCasting, no less[[/note]] who was hoping to draw out the real bomber by making himself out to be a kindred spirit.
* Michael Weston planned to do this in an episode of ''Series/BurnNotice''. While trying to score points with the boss of a gang, he sets up TheDragon to look like an undercover cop and then be the hero when he exposes him. Since the guy had no problem destroying valuable property just to scare people, Michael didn't feel too bad for the guy. [[spoiler: Turns out he actually was undercover. Oops.]]
* This trope has been used at least once on ''Series/{{Castle}}'', and probably several times. The protagonists are investigating a murder and an early suspect turns out to be an agent of the FBI or ATF who was investigating the victim (or employing the victim somehow, or investigating or another suspect) for their own reasons.
** The murder of a dog show judge leads the cops ([[AndZoidberg and Castle]]) all over the place. Eventually, they find a warehouse, where the victim's assistant claims that the guy was trying to cross-breed dogs. After digging around, they start to suspect that the victim was involved in bringing drugs from South America. They confront the "assistant", who immediately tells them that they will, in fact, find drugs hidden in the warehouse. He's a US Customs agent. The victim was employed to train drug-sniffing dogs (hence the drugs and the $10,000/month money transfers).
** Ryan does this in-universe in "The Wild Rover". If the audience didn't already know, that ending would've been pretty impressive.
* A mild version in ''Series/LieToMe'' where Foster starts dating a high school guidance councillor, only to get strange vibes from him. She then finds passports with different identities and evidence of drugs. After she confronts the guy about it, he admits that he's DEA, sent to uncover a school trafficking ring. He later reveals it to Cal as well, given that Cal can't help but stick his nose in other people's business.
* An episode of ''Series/TheFamousJettJackson'' shows an episode of the ShowWithinAShow ''Silverstone'', where all the world's bad guys are invited to a remote mansion by a mysterious new villain named Mr. Kilimanjaro. Throughout the dinner, they start arguing and trying to one-up each other, revealing all their recent and latest plots. It turns out that the whole thing was a setup by Silverstone (in disguise as Kilimanjaro) to get recorded confessions from these guys and grab them all at once.
* On ''Series/NCISLosAngeles'' Eric Christian Olsen's first appearance is as an MMA fighter and suspect called Jason Wyler. It's not until half way through the episode that Hetty reveals that he is Detective Marty Deeks, undercover.
** All the team members are highly trained and experiences in undercover work so this happens in-universe fairly often. Since they hate burning a cover identity, they will try to delay the reveal as long as possible. One of Callan's old girlfriends spent years believing that he was her brother's criminal friend who had to leave town after the cops got too close.
* In episode 4 of series 1 of ''Series/DeathInParadise'', the MsFanservice in a group of treasure hunters turns out to be an investigator from an insurance company, which had been defrauded by the leader of the group. Camille, one of the main police officer protagonists, had immediately disliked her and thought she was guilty (mainly because she caught her superior officer and [[{{UST}} potential love interest]], Richard, ogling the woman), and when the woman reveals her true identity, Camille [[InsaneTrollLogic declares that she was proven correct]].
* In one episode of ''Series/TheInvisibleMan'', Hobbes is revealed to have a history of StalkerWithACrush behavior toward his ex-wife, including suspicion of her boyfriends. He becomes suspicious of her current boyfriend, who has a criminal record, suspicions which seem to be born out when he and Fawkes catch the guy scheming with others to steal military tech and sell it on the black market. After they capture him, it turns out that he's an undercover FBI agent (and thus his criminal record is fake) and was involved in a sting operation which they [[NiceJobBreakingItHero nearly ruined]].
* ''{{Series/JAG}}'':
** The episode "Brig Break" has Meg Austin discover that [[spoiler: Petty Officer Quinn]] is an undercover agent for Navy Intelligence trying to infiltrate a group of gun runners. He ends up [[NoHonorAmongThieves getting killed]] by [[spoiler: Sergeant Lowell]] soon after Austin figures it out.
** PlayedForLaughs in "Boot". After everything she has put her through, Staff Sergeant Carrington is [[OhCrap stunned]] to discover that Private [=McEntire=], a problem recruit she had been singling out, was in fact Lt. Meg Austin. Austin assures her she knew it wasn't personal.
* On ''Series/PersonOfInterest'' one [=PoI=] is a robber who seems to be planning to murder a police officer. Reese sees the criminal breaking into the cop's house and is about to intervene when the cop's wife opens the door and greets her husband. The [=PoI=] is undercover in a gang of jewel thieves and he took some time off to see his family. Later on, the cop's cover is about to be blown so Reese outs himself as TheMole instead.
* In one episode of ''Series/CriminalMinds'' Morgan and Reid spot that the friend of a kidnapped girl's father is carrying a concealed gun; he's a Federal Marshal and the family are in the Witness Protection Program while waiting to testify against the Mob.
* In an episode of ''Series/{{Elementary}}'', Sherlock deduces that a member of a drug cartel is an undercover cop, who sneaks information to him under the pretense of staging a fight. [[spoiler: Unfortunately it turns out that said cop had [[BecomingTheMask Become the Mask]] in the worst way possible.]]
* ''Series/{{House}}'' had a patient brought in who was part of a drug-smuggling gang, who refuses to tell House where the hideout is as it might cause the upcoming raid to fail, despite House needing to know what he got sick from. His buddy (who doesn't know he's a cop) eventually lets them in, but [[spoiler:the cop's disease is fatal, and he dies without having blown his cover]].
* ''Series/FatherBrown'': In "The Owl of Minerva", Father Brown and Inspector Sullivan are cornered by the murderer and another member of the conspiracy, only for the other member to turn out to be an inspector from Special Branch who arrests the murderer.
* Practically OnceAnEpisode on ''Series/HillStreetBlues'', usually some combination of Detectives Larue, Washington or Belker -and less frequently Sergeant Goldblum- at the climax of a sting operation.
* ''Series/TrueBlood'': When Sookie first meets Eric Northman at Fangtasia, she listens in on the thoughts of other human customers in the bar and determines that one guy is an undercover cop and the place is about to be raided.
* Hilariously subverted in the fourth season of ''Series/TheWire''. Prez, formerly a cop [[spoiler: until he accidentally shot another cop]], becomes a school teacher, but Bubbles (formerly a police informant) sees him at the school, and not knowing Prez is no longer police, assumes Prez is setting himself up for this, and promises not to spill the beans. Prez, of course, has no idea what Bubbles is talking about.
* In ''Series/LawAndOrderSpecialVictimsUnit'', Amanda has a gambling problem and racks up a sizable debt with a local casino. When she's identified as a cop, a couple of guys take her to the back room and check her for a wire. They, and their boss, immediately assume she's a dirty cop and start blackmailing her in order to do things for them that only a cop can do. Throughout all this, she has to deal with an overbearing Irishman named Declan, who appears to be the casino owner's NumberTwo and her chief enforcer. At one point, she fails in a task and they threaten to expose her. In desperation, she offers herself to Declan, who sends his underling out of the room and turns on a camera, before seemingly pushing her down to his crotch level. At the end, he shows everyone the recording, where he actually stops short and tells her (without an Irish accent) that he's Lieutenant Declan Murphy of NYPD Vice. He doesn't care that she's a dirty cop, but he's willing to overlook it, if she helps him nail the casino owners. He uses the recording to get all the charges dropped from Amanda. For a while, he even becomes the head of SVU, although he still spends most of his time undercover. [[spoiler:He and Amanda have a fling, resulting in a pregnancy. She doesn't tell him until later and decides to raise the baby alone]].


[[folder: Music ]]

* In the video of Hobastanks' "Same Direction", which is a sequel to "The Reason" where the band stole a Ruby, the singer is revealed to be an undercover cop and then arrests his band mates.


[[folder: New Media ]]

* Occurred in the skits for ''The Egypt File'' VBS. The custodian turned out to be an undercover cop on the trail of a notorious artifact smuggler, [[TheMole who had been disguised as a cop]].

%%Please don't add that one play we're not spoiling. You know the one.


[[folder: Video Games ]]

* Agent Shepherd in ''VideoGames/TwistedMetal: Head On'' reveals himself to be FBI rather than take a wish from Calypso.
** John Doe from ''VideoGame/TwistedMetalBlack'' discovers that he's an FBI agent, but not until he gets his memory back after the tournament...and standing in front of the number two most wanted man in the world.
* Doll in ''VideoGame/SagaFrontier'', during Red's game when investigating Berva.
* A sidequest in ''VideoGame/FalloutNewVegas'' has you encounter a NCR Ranger in disguise as he runs a sting on a crooked quartermaster. He reveals himself after you run afoul of him, forcing you to either turn in the crooked quartermaster, fast-talk the ranger, or just blast him.
* In ''VideoGame/SaintsRow'', Troy Bradshaw is an undercover cop who infiltrated the Third Street Saints. He reveals himself after the rest of the gangs have been taken out by arresting Julius Little.


[[folder: Western Animation ]]

* In the ''WesternAnimation/{{Archer}}'' episode "Smuggler's Blues", Archer travels to Colombia to seek an alliance with the beautiful and feared cartel boss La Madrina, who turns out to actually be a high-ranking officer in the Colombian national police. She has him arrested for drug trafficking, but only after a night of heated passion.
* In one episode of ''WesternAnimation/DogCity'', the villain is posing as a school teacher to get into a mint under the cover of a field trip. He is thwarted when it turns out that only two of his students are ''not'' undercover cops.
* In the ''WesternAnimation/BatmanTheAnimatedSeries'' episode "Almost Got 'Im", as several of Batman's villains play poker at a seedy bar and exchange stories on how they had nearly killed Batman, Joker announces that he had just kidnapped Catwoman and was holding her at an abandoned catfood factory, where he planned to have her killed. Killer Croc then punches out Joker, and the other thugs discover that Croc is really Batman in disguise. When they decide to take him out, ''every other patron of the bar'' turns out to be a cop. The gathered cops, led by Commissioner Gordon and Detective Bullock, take down the villains, leaving Batman free to save Catwoman.
* Often happens in ''Franchise/ScoobyDoo''. They usually are working to take down the supernatural threat, but the kids usually beat them to it. Leaving the audience wondering how incompetent the officer has to be, since the target audience would be unaware of the rules of evidence required.
* The ''WesternAnimation/SouthPark'' episode "Butters' Bottom Bitch" has Sergeant Yates disguise himself as a prostitute and out himself to all the people who hire him. At the end, he ''marries'' a pimp and they live a happy life for a year before he outs himself.
* In an episode of ''WesternAnimation/TheClevelandShow'', Cleveland talks to what appears to be a teenage boy, asking him if he wants to be friends with Cleveland Junior. [[ICallHimMrHappy Taking it]] [[MistakenForPedophile the wrong way]], the "teenager", in a deep voice, says the code word "Boomerang" into a hidden microphone, and several police cars show up on the spot.