The Infiltration

Because, after all is said and done, an infiltrade must make an investigation on his own conscience.

— A review of The Molly Maguires

The protagonist, typically a cop or secret agent, must get "inside" a bad-guy organization and pass as a bad guy to accomplish a goal. Sometimes it's the other way around, where the bad-guy poses as a good guy.

This is not just when they have to disguise themselves temporarily, but spend significant time among the villains and the Mooks themselves and even take on a role in their organization. Spending so long among the enemy can cause a "Not So Different" Remark or, in a more severe case, lead to Becoming the Mask. Another risk is if the agent somehow loses his link to the parent organization, in which case can they can end up Trapped Undercover. Good guys may be tested by the bad guys demanding that they kill someone to prove they are a criminal.

When a team must infiltrate, the story often bears resemblances to The Caper or The Con. Girls Behind Bars is usually a case of infiltration.

A common twist is to make the protagonist kill or do something to his old friends. The Hero will fail here, usually, but the Anti-Hero of the sociopathic sort or a Cowboy Cop type will often pass. Spy work is also crucial, because Only the Knowledgable May Pass often comes into play.

When infiltration is unnecessary, the heroes may decide to "slip by Right Under Their Noses" anyhow.

Contrast The Mole, where, as noted above, a bad guy is posing as a good guy. See also Dressing as the Enemy (which sometimes involves stealing a henchman's clothes) or If You're So Evil, Eat This Kitten! (when a character undercover is given a rigorous test to prove their villainous credentials in an effort to gain the bad guy's trust). Sometimes involves becoming a Fake Defector. One subtrope is Impersonation Gambit, where the hero steals the identity of a real person the bad guys have never seen. Flock of Wolves is a comedy trope where everyone else turns out to be "infiltrators" as well. Super-Trope of Black-Tie Infiltration, where the infiltration is done at a party or other social event. If this happens on a smaller scale, compare Delivery Guy Infiltration, Surprise Inspection Ruse and/or Janitor Impersonation Infiltration. Police infiltration doesn't tend to get far if the bad guys Can Always Spot a Cop, however. The way for the good guys to get their mole to pass is to use someone with a checkered past who was previously associated with the criminal milieu. For large-scale infiltrations, where the good or bad guys have people infiltrated everywhere (or just in strategic locations, but the point is that you don't know who is and who isn't an agent), see We Are Everywhere.

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Examples:

Anime and Manga

• In Case Closed, many members of the Black Organization are revealed to be undercover agents sent by various police and intelligence agencies trying to destroy the organization from the inside. First, FBI agent Shuichi Akai used to be known as Rye as a member of the Black Organization. We also have Rena Mizunashi (code name Kir, real name Hidemi Hondou), who is with the CIA. Then there is Tooru Amuro (code name Bourbon, real name Rei Furuya), who is from the Japanese secret police.
• In Girls und Panzer, Yukari regularly sneaks into opposing schools' ships to gather intel for upcoming matches. She's managed to do it to Saunders, Anzio, Pravda and BC Freedom, with the American and French-themed schools actually cottoning on to her spying. The former's leader let it pass because it was funny while the latter used the opportunity to feed Ōarai some bogus intel.
• Treated like Serious Business, and Played for Laughs, in episode 3 of Is the Order a Rabbit?, after Chiya shows an advertisement flyer to the other girls of where Sharo works, and thinks it's a seedy place. They all attempt to peek in the cafe to see what kind of illegitimate business dealings go on in there...only for them to find out it's a regular tea cafe, and Sharo spots them peeking through the window immediately
• In My Hero Academia, Hawks infiltrates the League of Villains to find out what they’re planning. He pulls it off quite well and they never suspect anything.
• This is the basic plot of the Psychic Squad Spin-Off, Unlimited Psychic Squad. Andy is an agent of an American Esper Intelligence organization sent to infiltrate the Esper terrorist group PANDRA. Comes complete with "Not So Different" Remark and hints of Becoming the Mask.
• Played twice in Tantei Team KZ Jiken Note's The Valentine Knows arc, as it involves a group of Japanese Delinquents:
  • Kuroki shows up in front of the rest of Detective Team KZ in whole Japanese Delinquents gear when he reports the activities of the group of delinquents they are investigating. Provided his role as The Team's Information Broker, it implies he does that briefly.
  • The reason this case started in the first place is because Sunahara is sighted among that group. Turns out his foster family lost some 6 million yen in a scam, and he decides to join them for the sake of investigation. He was outed by Onozuka, nearly killed, but saved by the The Team.

Comic Books

• In the Astro City arc "The Dark Age", Royal and Charles Williams end up joining the villainous organization Pyramid (on separate occasions) to get the man who killed their parents.
• Bronson launches a very brief one in Copperhead by stripping down, entering the brothel, and grabbing the attention of a client.
• In Invasion! the Durlans use their shapeshifting abilities to mimic people in various teams and agencies in preparation for the coming invasion.
• Mortadelo y Filemón: "Objetivo: Eliminar al Rana" and "El Tirano".
• Brubaker's Sleeper (WildStorm) is one of these with the added twist of his handler falling into a coma and leaving him trapped behind enemy lines with no one to report to.
• This was The Unknown Soldier's whole career. Impersonate someone, get inside the target area, terminate the target (officer, secret weapon, intelligence gatherer, Etc). Sometimes he could get the target's protectors to terminate the target for him.
• The Ultimates: The Chitauri infiltrated SHIELD. Actually, it was just some strategic points, but it was quite enough: intelligence agencies are filled with people with Blind Obedience, who don't really stop to question the orders they receive.
• Wonder Woman Vol 1: Steve Trevor fairly regularly cozies up to the villains and infiltrates their organizations in order to get enough intel to bring them down or free hostages they've taken.
• X-Men comics: Cyclops goes undercover as Eric the Red, redirecting his Eye Beams to appear that he has energy weapons in his armor's hands. (Both the Eric the Red and Red X identities were used later by actual villains, and the identities are now associated with them, not the original disguised heroes.)

Fan Works

• In the Temeraire fanfic Black Wings, Black Sails, when Laurence takes the crew of the Allegiance prisoner at the behest of the Tswana and presents the prisoners' options- prisoners of the Tswana to be used for an undecided fate, or a year of service in Laurence's pirate crew -Granby takes the latter option, hoping that he'll have an opportunity to get aboard Laurence's flagship and free Dayes from confinement. It's unclear if Laurence is aware of this possibility, but nonetheless, it doesn't seem to be working out for Granby, as he winds up holystoning the deck on a different ship and accompanying Laurence into Capetown for supplies.
• In Faded Blue, Greg moved to Beach City to spy covertly on the "bad guys" - the Crystal Gems - made all the easier when Rose Quartz develops a crush on him. Only Greg starts realizing that for supposedly violent, evil warriors, they're quite likable and protective.
• In The Prayer Warriors Battle With the Witches, Michael sneaks into Hogwarts, posing as a student, in order to find out if Hogwarts is connected with the English government and whether it is planning any attacks on Christians. He's also told that if he's ever forced to do anything un-Christian, he must pray for forgiveness.
• In the Pony POV Series Wedding Arc, on several occasions the Mane Six need to act as if they're brainwashed to sneak around during the Changeling invasion. Misfit Actual takes this a step further and exploit the fact they're the only Guards in Canterlot that presently aren't Changelings, and Running Gag's Omniglot ability allowing him to copy the Changeling's language flawlessly, to pose as Changelings and undermine their invasion.
• The Steel Ministry is about Marsh from Mistborn infiltrating the Steel Ministry. As a Seeker, he can sense Allomancy, and is put to work searching for illegal skaa Allomancers. When he does find one, he is distressed that he had to turn him in because the other Seeker on his team would suspect him if he didn't, and is only slightly comforted by the thought that the man was doomed without his help.

Film

• Alibi features an undercover cop who assumes the identity of an alcoholic stockbroker and gains entry into the inner circle of a gangster ring.
• In The Departed, Leonardo DiCaprio's character plays the trope straight when infiltrating the Boston underworld. Matt Damon, his counterpart, plays The Mole.
• Diamonds Are Forever has James Bond infiltrating a diamond-smuggling operation.
• Donnie Brasco, in which an FBI agent infiltrates a Mafia family. This one was Truth in Television.
• Dungeons & Dragons: The Book of Vile Darkness, a TV Movie sequel to the Dungeons & Dragons (2000) films centers around The Hero infiltrating group of villains in order to rescue his father.

• Also Truth in Television: The Infiltrator, about a US Customs agent who wormed his way into the Escobar drug cartel to help take it down.
• Reservoir Dogs has the main characters trying to figure out which one of them is an undercover cop. Sure they can figure it out, if the right guy lends them an ear.
• Scanners: Cameron Vale poses as one of Darryl Revok's scientists to infiltrate his chemical company. While there, he discovers Revok's 'Ripe Program', a master plan to create a new army of psychic scanners by bribing physicians to prescribe Ephemerol to their pregnant patients.
• Serenity has Simon Tam infiltrating an Alliance-operated military research facility to free little sister River from continued Super-Soldier experimentation and Mind Rape.
• Sky High (1922) is about a Border Patrol agent who infiltrates a human trafficking gang that smuggles Chinese immigrants over the border from Mexico.
• White Heat has an undercover agent posing as a prison inmate and subsequently joining Cody Jarrett's gang.

Literature

• Severus Snape from Harry Potter most certainly qualifies for many reasons:
  • During the Attack on Godric's Hollow, when Lord Voldemort killed Harry's parents, James and Lily, Snape was devastated over his loss of Lily; and therefore, he sided with Dumbledore to protect young Harry.
  • Later, after he killed Dumbledore, he seemingly sided with the Death Eaters, until Voldemort murdered him with Nagini, thinking him as master of the Elder Wand.
• In Poul Anderson and Gordon R. Dickson's Hoka stories, Alex Jones infiltrates the Hoka Pirates to prevent actual fighting from breaking out.
• In Russia and probably all other post-Soviet countries, this trope is literally synonymous with the name of Stirlitz, the main character of a spy novel series and an incredibly popular television series based on it. He's basically a Soviet spy who is skilfully pretending to be a SS-Standartenführer.
• Richard Adams' Watership Down. Bigwig uses this technique as part of Hazel's plan to free some does from Efrafa.
• The murder Sherlock Holmes investigates in The Valley of Fear centers around a Pinkerton agent who infiltrated a criminal gang in the United States by posing as a murderer and counterfeiter, before turning on his supposed allies and helping the police break up their operations. It's Truth in Television: Sir Arthur Conan Doyle based this story on a real-life Pinkerton agent (an agency of private detectives often used in the days before the government created the FBI) who infiltrated and then broke up a gang of militant miners known as the Molly Maguires in the 1870s.
• In Brian Jacques' Martin the Warrior, Brome gets into Marshank by pretending to be a sea rat.
• In Sandy Mitchell's Warhammer 40,000 novel Scourge the Heretic, Keira poses as a noblewoman to infiltrate a Chaos cult. Meanwhile, Kyrlock and Elyra attempt to infiltrate a smuggling operation: Kyrlock by pretending he deserted and Elyra posing as a servant running away from a mistress whose husband she had slept with and whom she had robbed.
• Many times in the X-Wing Series. The Rogues pass as Imperial civilians to get on Coruscant. The Wraiths pass a warlord's subjects, then as stormtroopers, then later as pirates that the warlord wants to recruit. The Rogues set themselves up as members of one Imperial faction.
• In G. K. Chesterton's The Man Who Was Thursday, Syme is taken to an anarchist meeting and, being a policeman, sets out to infiltrate.
• Done twice in the Age of Fire Series. AuRon infiltrates the Circle of Man's main base to end their enslavement of dragons and to protect his friend's nation. In the next book, Wistala does the same to the Wheel of Fire Dwarves, this time to get revenge on those who slaughtered her family.
• Septimus Heap does this in Darke by disguising in Darkenesse to get into the Darke Halls and rescue Alther Mella.
• Katya is used in the task for most of the Paladin of Shadows series, and is being trained by Jay to improve her abilities in it starting with Choosers of the Slain.
• In The Clockwork Angel, having been given absolutely, totally false information that de Quincey is the Magister, the Clave devises a plan to have Will and Tessa enter one of de Quincey's lavish parties where he tortures mundanes like Nate by having Tessa transform into Camille Belcourt. At the sign of de Quincey breaking the Law, Will is supposed to signal the Clave so that they can kick some vampire ass.
• Harry Bosch novels:
  • Trunk Music: Bosch arrests Mafia mook Luke Goshen for the murder of Tony Aliso when he finds the murder weapon hidden in Aliso's room. Harry gets into a lot of trouble later when he finds out that Goshen is actually an undercover FBI agent who is definitely innocent of the murder.
  • Two Kinds of Truth: For the first time in his 40 years in law enforcement, Harry goes undercover. He makes himself out to be a homeless opioid addict in order to get the goods on the Russian pill smugglers who killed the Esquivelas.
• Wet Desert: Tracking Down a Terrorist on the Colorado River: The bomber dresses himself and his truck as that of an elevator maintenance company to bypass security at Glen Canyon Dam.
• Lucky joins the Wild Pack in second Survivor Dogs book in order to find a way for his friends can drink from their lake. He soon finds out that staying loyal to his old pack (including his sister Bella) is harder than expected.
• This happens twice in The Mental State. The first time, a police officer pretends to be a junkie inmate in order to infiltrate a prison drug ring. This backfires completely when the main character, Zack, uncovers the truth, steals his mobile and blackmails him into becoming a junkie for real. The second time happens when Jeremy throws himself on Saif's mercy after he steals from Zack. This turns out to have been a ruse for him to infiltrate Saif's gang and gather information to help bring down his criminal organisation.
• Vin and Marsh infiltrate the nobility and Steel Ministry respectively in Mistborn: The Original Trilogy, Vin as a rural lord's niece and Marsh as an eager adult acolyte. Vin doesn't get caught, but things go badly for Marsh, whose flayed corpse is found in a safe house next to a letter explaining that the Inquisitors suspect him. He didn't get caught, either. Turns out he impressed his superiors so much with his Seeker abilities and general acumen that they turned him into an Inquisitor. They still don't suspect him, and he stays undercover long enough to kill all the Inquisitors in their sleep.
• A Scanner Darkly: Bob Arctor is a cop undercover to investigate about the production of Substance D.

Live-Action TV

• Used by both the good and bad guys on 24. So much so that you start to wonder if anybody on that show ever heard of a background check....
• On The Blacklist this is Tom's specialty. As a teenager, he was recruited by The Major and trained to be a perfect undercover operative. When he assumes a new persona his performance is usually flawless. He is able to fool Liz for years into thinking that he is a mild mannered teacher and even a full scale FBI investigation is unable to break through his legend. In a latter assignment he transforms himself into a neo-Nazi so he can get inside a neo-Nazi weapons smuggling ring.
• Happens often in Burn Notice, although Michael occasionally takes the identity of a potential business associate of that episode's villain rather than a member of their group.
• Charlie's Angels: Given their work as Private Investigators, a lot Charlie's plans involve the Angels and Bosley going undercover and working for the villains they're trying to take down.
• Chuck has Mary Bartowski in the backstory and Sarah in season 4 undertake these by pretending to do Face-Heel Turns.
• Class of '09: Poet is skilled at undercover work, infiltrating a corrupt police department so well it results in the greatest FBI bust of dirty cops ever.
• CSI: NY: Det. Lovato's backstory is revealed in "Blood Out." She'd spent 17 months as a member of the Trinatarios, a Dominican street gang known for drug dealing, while assigned to the NYPD's Narcotics unit. When her cover was blown, she got reassigned to Homicide and became Flack's partner.
• Doctor Who: In "Kerblam!", the Doctor, Ryan, Graham and Yaz infiltrate the titular MegaCorp's warehouse facility by posing as new hires, with the help of the sonic screwdriver and psychic paper, to find out who inside the facility sent the Doctor a message for help inside a package she received.

• Sayid infiltrates a terrorist cell in the flashbacks of the Lost episode "The Greater Good".
• The Hardy Boys/Nancy Drew Mysteries: "Game Plan", in Season 3, has Frank Hardy joining a criminal organization by pretending to be a drifter looking for work. At one point, he seems to have gone totally over & sold out the Feds, to the point of pulling a gun on his brother Joe.
• Law & Order: Special Victims Unit:

• When Mariska Hargitay was on maternity leave, Benson's absence was explained by saying that she was infiltrating an eco-terrorist group. In the aptly-named episode "Infiltrated", which marked Hargitay's return to the show, we briefly see Benson in this role.

• On Legends Martin Odum is an FBI agent who specializes in deep cover undercover work. He regularly assumes new identities and rarely breaks his cover. However, he starts to suspect that his identity as Martin Odum is just another of his legends and that he forgot who he really was due to amnesia from an accident. He was actually a MI-6 agent and his new identity is a form of witness protection after he was almost killed infiltrating a mercenary group. Season 2 has him try to renter an old identity that he has forgotten and try to fix some of the mistakes he made when he tried to infiltrate a group of Chechen criminals with ties to terrorists. It is then reveals that he is actually a Russian who was trained from childhood to pretend to be British so he could then infiltrate MI-6 and thus he has been living this trope for most of his life.

• In Made For Love, an FBI agent whose real name is Jay takes on the identity of "Jasper" to infiltrate a powerful tech company and reveal its location to the feds, who believe their dealings are unethical but can't actually find the place.
• Major Crimes introduces Detective Amy Sykes in the first episode as a member of the LAPD's SIS (Special Investigation Services) division, which handles surveillance and undercover assignments. She helps the Major Crimes Division with the case and transfers in afterwards. If they're doing a stakeout, she's almost always involved.
  • The middle of Season 5 introduces Wes Nolan, who's been undercover for more than five years in a Neo-Nazi group connected to the recent murder of a witness and a subsequent courtroom shootout. There's a debate on whether to pull him out or use him to gather more information. They end up doing both, and when he does break his cover, he gets a member of the group to flip. He is also transferred to Major Crimes.

• Callen of NCIS: Los Angeles makes his careers, plural, out of this trope, and undercover work is a specialty of the L.A. team.
• New York Undercover focuses on two NYPD detectives infiltrating the city's gangs.
• The Night Manager is a story about an infiltration, the psychology of the infiltrator, and the dangers of possible betrayal at multiple levels.
• The Stargate SG-1 episode "Off the Grid" requires a member of SG-1 to go undercover as a drug smuggler. After a hilarious argument about who would be the most convincing, Colonel Mitchell pulls rank and decides he's going to do it. Mitchell's act fails spectacularly and the scene cuts to the team running away from the bad guys and Teal'c saying "I did advise you were a most unlikely drug smuggler, Colonel Mitchell."
• "Mirror, Mirror", one of the most popular Star Trek: The Original Series episodes, featured the good guys from the Enterprise having to spend some time among their evil universe counterparts.
• The Star Trek: The Next Generation first-season episode "Conspiracy" has Picard and Riker pretend they were under the influence of an alien parasite.
  • The "Gambit" two-parter has Picard doing an impromptu infiltration to discover why a group of pirates is ransacking archaeological sites by convincing them he was a smuggler.
• True Detective:
  • Played out with lots of tension. Rust, a former undercover cop, decides to go back into his undercover persona "off the books" in order to get to a specific person of interest. Although he's done the infiltration before, the tests he has to run through such as doing drugs that have been previous shown to mess with his head and sense of awareness to varying degrees to prove his bona fides, and the massive mess that erupts when things fall apart, make it harrowing to watch.
  • In season two, Ani pretends to be a prostitute in order to infiltrate a secret party where rich and powerful men get to network, close deals and participate in Hookers and Blow orgies. Things quickly go bad since all the prostitutes are given a date rape drug that makes them weak and unable to resist. Ani almost gets raped and killed but manages to stab her attackers with a knife and escape.
• Occurs quite often on Walker, Texas Ranger:
  • Season 4's "Break-In" has Walker and Trivette posing, respectively, as an inmate and a guard in a federal prison to gather evidence on an inmate who ordered the deaths of a witness (on whose testimony he was convicted) and two Rangers, but run into complications when the convict and prison administration are found to be in cahoots.
  • "El Coyote", also in Season 4, had Walker going undercover with Mexican agent Jesse Rodriguez as Mexican peasants to infiltrate a slave-trading operation.
  • In Season 6's "Forgotten People", when an old friend of Trivette's staying at a nursing home turns up dead, C.D. pretends to be an Alzheimer's patient to investigate, upon which they find that the nursing home turns out to be a front for an illegal testing facility where its patients are being used as guinea pigs to have variations of an illegal Alzheimer's drug put on the market. C.D. later makes a new friend during his time there, who is also undercover for the same reason.
  • Season 7's "The Principal" had Walker and Trivette posing as a high school's new principal and head of security after said principal, who was an old friend of Walker's, was murdered by a villainous shop teacher dealing drugs, and busted the former head of security who was thought to be the ringleader.
  • "livegirls.now" (also in Season 7) had Trivette's new girlfriend being kidnapped by a gang of Sex Slave traders along with other aspiring models and about to be auctioned off. Walker, Trivette and Alex's only means of finding the kidnappers is by getting into the auction and tracing their location. Trivette takes on the job of being one of the bidders, and they needed the code from the photographer involved in the scheme after he was arrested by Walker. Trivette's cover is Kim Soo Park, a Korean industrialist who is currently serving 10-20 years for espionage; the arrest was scrubbed off his record so the kidnappers don't know what's going on. The trace is a success, but it hits a snag due to the kidnappers catching on to the ruse.
  • "Fight or Die" in Season 8 has Walker, Gage and Trivette posing as inmates (former two) and a guard (Trivette) to bring down an underground prize-fighting ring, where the warden and a corrupt promoter are forcing inmates to fight for their lives in mixed martial arts-type matches.
  • Occurs in both plots in Season 9's "Unsafe Speed". The main plot has Gage and Sydney going undercover as bikers to bust up a methamphetamine lab, but to access it, they have to be initiated into the gang through a series of rigorous tests, and among them is killing a Texas State Trooper, but the Trooper agreed to participate in the covert operation, having survived his gunshot wounds, due to wearing a Bulletproof Vest. The B-plot had Trivette pose as an unqualified trucker to nail a corrupt DPS Driver License Division employee who was illegally issuing trucker licenses, one of whom, who ended up killing a family of three, alerted the Rangers to the trafficking operation conducted by the bikers.
• The entire premise of Wiseguy, in which a cop adopts a fake identity as a bad guy and infiltrates organized crime outfits.
• This is the entire premise of Undercover (2019). Two cops spend months undercover trying to infiltrate a major drug operation in order to collect enough evidence to arrest the leader.

Pinball

• In order to fulfill Safe Cracker's title, you must first get into the vault the safe is located in. There are three ways of doing so - the front door, the roof, and the cellar.

Pro Wrestling

• Early in the second season of Lucha Underground it's revealed that Cortez Castro, a member of the thuggish heel wrestling team The Crew, had been an undercover cop all along.

Tabletop Games

• Everyone in Paranoia is trying to do this at all times, due to a combination of Gray-and-Grey Morality and City of Spies. Swapping sides is not uncommon.

Video Games

• In Betrayal at Krondor, James and Locklear pretend to be Quegan mercenaries to infiltrate the Big Bad's army in order to deactivate the Rift machine through which more of that army is arriving each minute.
• Dragon Age: Origins: After the protagonist gets captured (avoidable, if you can win one of the game's toughest fights), you are given two options: Break out on your own, or select two companions to control while they do this. Their different bluffing attempts are some of the funniest moments in the game, like Sten and Oghren's circus act.
• In Final Fantasy VII, when Aerith(s) was kidnapped by Shinra Corp, Cloud, Barrett, and Tifa all try to do this in order to save her from Shinra.
• Subverted in Infiltrating the Airship from the Henry Stickmin Series; while the title implies the main character, Henry Stickmin, is going to infiltrate an aircraft owned by an evil organization named the "Toppat Clan", he does not go undercover as a Toppat member in the actual game, and the one time he is mistaken for a member of the Toppat Clan, he ends up leaving in an escape pod.
• Mentioned in Hidden City when Mr. Black decides to infiltrate a Shadow Cult meeting to confirm that his former assistant Violet had indeed defected to the cult. The player character helps him draw a tattoo of the Cult's symbol to allow him entry into the meeting, but the infiltration itself happens off-screen.
• In Mass Effect 2, in order to recruit "Archangel" for their mission, Shepard has to first pose as a freelance mercenary, joining the other mooks-for-hire hired by the three major mercenary groups on Omega, hellbent on taking Archangel out. After taking a moment to subtly sabotage the mercenaries efforts and equipment, Shepard heads across the bridge to Archangel's compound, before immediately turning around and begin taking out their former "allies".

• Several [PROTOTYPE] missions. Even in non-mission military consumptions, there's a huge EP bonus for acquiring a skill and leaving without alerting the troops.
• In Sleeping Dogs (2012), Wei Shen is an undercover cop trying to take down the Sun On Yee Triads in Hong Kong.

• Star Wars
  • In Star Wars: The Old Republic, infiltration becomes the endgame goal of most light-sided Imperial characters in one form or another, with Sith Warriors/Inquisitors wanting to reform the Empire from within, Imperial Agents erasing their identity with the Black Codex so they can help the Empire without having to worry about Sith infighting, and Bounty Hunters defecting from the Empire completely and becoming Republic moles.
  • In Knights of the Old Republic the Player Character, looking for a MacGuffin, has to infiltrate a Sith Academy, posing as being interested in becoming a student.
• In the Thief: The Dark Project mission "Undercover", Garrett infiltrates the Hammerites by passing as a novice. This is the only time he does this though, since the Hammerite church is far too well-defended for even him to sneak into normally. He also needs help from several inside men to pull it off (needing both a genuine novice uniform and a forged letter of admittance), and once inside must be careful to not be caught doing something a Hammerite novice shouldn't be doing.
• In World of Warcraft, the Cape of Stranglethorn questline involves you infiltrating the Bloodsail pirates on behalf of Booty Bay. At one point, they do ask for a test of loyalty - you need to kill a tauren who is a higher-up in Booty Bay, and bring back his head. Fortunately, they're too stupid to tell a (female) cow's head from a (male) tauren head, so you decapitate a cow, slap a pirate hat on her head, and hand it off.
  • In the Mount Hyjal quest chain, you have to pose as a Twilight's Hammer initiate to find out where Jarod Shadowsong is being kept.
  • In the Alliance "Operation Shieldwall" questline, you have to disguise yourself as a Horde soldier and get information from a Horde interrogation of a captive Mogu.
• In Saints Row, Troy Bradshaw does this. He's an undercover cop who joins the Third Street Saints. He gets a little too into his role, but eventually reveals himself by arresting Julius.

Webcomics

• Bob and George: Proto Man as Break Man
• In Strays, Prince Holland in action.
• In Impure Blood, Dara chases after the innkeeper because of her council membership.

Web Original

• In Worm, Taylor, after being mistaken for a supervillain on her first night out in costume, decides to infiltrate the supervillains that she helped with the intention of betraying them to the local superheroes once she's gathered information on the group. As time goes on, however, she finds herself Becoming the Mask and becoming real friends with the Undersiders.

Western Animation

• In Avatar: The Last Airbender "The Boiling Rock", Sokka and Zuko dress up as prison guards to get back Hakoda (Sokka's father).
• An episode of Inspector Gadget featured this, appropriately titled The Infiltration, with M.A.D. Master of Disguise Presto Change-O impersonating Inspector Gadget to sneak into a top secret worldwide police conference in London. The viewing audience can tell the phony Gadget from his stereotypical bad English teeth and crazed eyes, while the rest of the cast initially can't, until the real Gadget accidentally bonks Chief Quimby with his Gadget Mallet.
• In the Justice League episode "Task Force X", the titular protagonists must get "inside" a bad-guy organization (The Justice League Watchtower) and pass as mooks to steal a MacGuffin, only this episode is an inversion because this is a Villain Episode, but given we are seeing things from the villains' perspective, and the Justice League acts invokes Beware the Superman, this trope seems played straight.
  Colonel Flagg: This tower is so big and has so much staff in it no ones is going to notice us... unless one of you do something stupid.
• The Legend of Korra "The Revelation." Mako and Korra disguise themselves and sneak into an Equalist rally.
• Spoofed in a short on OH Yeah! Cartoons, in which a crime-solving doughnut infiltrates a criminal organization under the guise of a new recruit to save his fellow officer. As the doughnut unties him, the officer says "I thought for sure you were in that box of doughnuts!". The doughnut responds, "Huh...never thought of that."
• In the episode "Kennel Kittens Return" of Pound Puppies (2010), Squirt "volunteers" to be disguised as a cat to retrieve the team's stolen invention from the rival cat organization.
• Elisa does this a couple times in Gargoyles, both times involving uncovering operations by mobster Tony Dracon.
• In the third episode of TaleSpin's pilot series, Plunder & Lightning, Kit Cloudkicker pretends to betray Baloo, Molly and Rebecca in the Iron Vulture to his former mentor Don Karnage, to allow them to escape. The fake deception is so convincing and surprising that Baloo believes himself betrayed, and angrily leaves Higher For Hire with the SeaDuck to Louie's to party his cares away, until he hears Kit desperately radio for help in the fourth episode.
• Teen Titans does it twice:
  • Cyborg enters the HIVE Academy under the guise of "Stone" to find out what secrets they're planning next. Later, in a mission against the HIVE with the Titans, he is beset by the HIVE's top agent, Bumblebee, only to find that she is a spy, (though she's more of a Fake Defector, as she has not donned a new identity for the mission). When Brother Blood finds out he rhetorically screams, "Was anyone at my school actually there to LEARN?"
  • On another occasion, Robin goes undercover in Slade's organization as Red X, but Slade sees through the deception.
• The entire concept of Punch/Counterpunch of Transformers: Generation 1, an Autobot spy who has the ability to adopt a Decepticon robot mode. In the Japanese Transformers: ★Headmasters continuity, he had even managed to become firmly entrenched in the Decepticon ranks as Scorponok's closely-trusted informant.
• Young Justice:
  • One episode had Superboy and Miss Martian infiltrate a maximum security prison for supervillains in order to prevent an impending jailbreak.
  • The second season had a major Story Arc where Artemis and Aqualad infiltrated the Light to discover and sabotage their plans. (Though Artemis was the only one who made a new identity. Aqualad just pretended to defect.) As an added wrinkle, most of the heroes were kept in the dark about the infiltration plan. This led to some friendly fire problems...

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