• In the Death Note manga (and anime), it's revealed that a second Death Note made its way to Earth. Light eventually takes advantage of this and works with accomplices more than once.
• In Sword Art Online, the perpetrator of the "Death Gun" killings in Gun Gale Online is revealed to be two people: someone controlling the in-game avatar, and a real-world accomplice who murders the player at the same time the avatar is killed to simulate the effect of a "magic gun that kills you in real life." But the real twist is that the government investigation afterward reveals there was a third partner in the loop who managed to evade authorities.

• Rather confusingly done in The Long Halloween. When the Holiday Killer is apprehended and revealed to be Alberto Falcone, he tells the police that there was another Holiday Killer, but he refuses to elaborate. Batman interprets this as a reference to Harvey Dent aka Two-Face, who had killed Carmine Falcone on Halloween and thus (metaphorically) inherited Holiday's mantle. But in the very last scene, Harvey's wife, Gilda, monologues that she was actually the one responsible for Holiday's first victims. Whether they were telling the truth, or had simply lost touch with reality due to grief, is not entirely clear.
• Nick Fury, Agent of S.H.I.E.L.D. (1968): The first issue opens with a variant of this. Fury breaks into a building but is shot dead by a masked man who catches him by surprise. It's then revealed that 'Fury' was actually a 'Life Model Decoy' android duplicate, and the masked man was the real Nick Fury - it was all a Fake Action Prologue, a training exercise to test the android's abilities. But then it's revealed that the L.M.D. was shot four times, and Fury only fired three - the villain of the story, Scorpio, has stealthily interrupted the training exercise with a simultaneous Assassination Attempt, assuming that he was shooting the real Fury.

• The mastermind of Danganronpa Another turn out to be three people: Akane Taira and her master Yuki Maeda, aka Utsuro, working together as subordinates of Junko Enoshima.
• Super Danganronpa Another 2:
  • Chapter 3: Both Hibiki and Kanade are the culprits behind Setsuka's murder, as they both stabbed her at the same time with their perfect synchrony. Downplayed by the fact that Kanade planned the entire murder, and Hibiki could not disagree.
  • Chapter 4: Nikei is the Arc Villain of the case as he goaded Yuki into cutting Shinji's throat, followed by Sora attempting to cut Shinji's throat again using an unconscious Nikei. But Shinji himself is considered the culprit as he eventually killed himself to save all of them from execution.
  • Chapter 5: Mikado poisons Teruya's food and pins the blame on Iroha, with Iroha herself believing she did it and actively helping set up the crime. Teruya goes ahead with it as a Heroic Sacrifice to screw Mikado over.

• In Black Rat, it turns out there are actually two different killers wearing the rat mask: Asuka's sister Akane, and Creepy Crossdresser Kengo. At the end of the film, after Akane and Kengo have both been killed, Misato dons the mask to kill the last survivor Saki.
• Blood and Black Lace: There are two people under the featureless mask at separate times Massimo killed some of the women, and Cristina killed the others to draw the police's attention away from him.
• At the end of Boar, the giant boar has been killed and the survivors drive away. However, as their truck pulls out of sight, a second giant pokes its snout of the undergrowth and snorts angrily.
• Used in Hellnight. A bit of an odd example as the legend that surrounds the setting tells about one "deformed guy hiding in the house", and doesn't explain who the second deformed guy is.
• Subverted in Hot Fuzz. At first Nicholas Angel suspects the Obviously Evil local supermarket manager Simon Skinner of being behind the string of mysterious deaths, but he has a watertight alibi. Just when Angel realizes that there must be more than one killer, he's attacked by Skinner's brutish thug, who tells him to rendezvous at a castle after believing Nicholas to be disposed of. Once Nicholas gets there, it turns out that in fact almost the entire town is in on it.
• It is revealed two thirds into Just Before Dawn that the fat redneck psycho killing the cast has an equally fat psycho twin, and they work together in getting rid of people trespassing their family's territory.
• When the killer crocodile is captured in Lake Placid, another one immediately appears. The second one gets shot, but it later turns out that the second, smaller crocodile was male...
• Murder Mystery:
  • Nick's original theory has Charles and Suzi conspiring (which they are, but unsuccessfully).
  • Then he theorizes it's Grace and Tobias, which is half right.
  • The actual killers are Juan and Grace.
• Played with in Psycho II, wherein Lila Loomis and (initially) her daughter Mary are trying to drive Norman Bates back into insanity and murder by impersonating his seemingly long-dead mother (i.e. the source of his troubled mental state), while Emma Spool simultaneously commits a series of murders and claims to be Norman's actual mother. Ultimately, Mrs. Spool kills Lila, Mary tries to kill Norman based on the mistaken assumption that he was actually responsible for the murders (and becomes the main police suspect for them herself as a result), and Norman finally rejoins the fun by killing Mrs. Spool and resuming his life as a slasher.
• The Rip: There are two primary corrupt cops behind Jackie's murder and all the events of the night: Mike Ro, who is revealed first, and Matty Nix.
• Subverted in the first Scary Movie 1. There are three separate killers all adopting the Ghostface persona. The first two are two gay teenagers (although one of them is in denial about it) working together, while the "real" killer is a cop Obfuscating Stupidity who kills the former two for trying to upstage him.
• In the first Scream (1996), it turns out that there were two Ghostface killers working in tandem to terrorize the town of Woodsboro. This was also true in Scream 2, but by then it was expected. (However, Scream 3 had only one killer. But Scream 4 returned with the duo of Ghostfaces. And Scream VI upped the ante with three.)
• In the BBC television film Sherlock Holmes and the Case of the Silk Stocking, the murderer turns out to be a pair of identical twins, which enables them to always have an alibi when they kill.
• After the killer Santa Claus's identity is revealed in To All A Goodnight, it is shown to the audience that there is also a second one.
• In the 2014 meta-sequel to the 1976 movie The Town That Dreaded Sundown, the "new" Phantom killer turns out to be two men working together: the first victim who faked his death with the help of the second one, the sheriff deputy.
• In the sex comedy Video Vixens, a film-within-the-film, an X-rated Dragnet parody, involves a serial rapist who is actually identical twins; one would go out and rape someone while the other is seen in public doing something mundane as an alibi. The next night they'd switch places. (Yes, despite the description, it's a comedy.)

• In the Choose Your Own Adventure book Who Killed Harlowe Thrombey?, it turns out that the crime was committed by the titular character's niece and her fiance - he stole a bottle of arsenic from Thrombey's greenhouse, and she spiked his bottle of brandy with it.

• A Russian joke goes: the Chinese army desperately tries to cross a mountain pass guarded by one Russian soldier. 100,000 Chinese try to storm the pass, no one returns. 200,000 Chinese try to storm the pass, no one returns. 500,000 Chinese try to storm the pass, one badly wounded soldier returns and yells: "Ambush! There are TWO of them there!"

Authors:

• This was one of Agatha Christie's favorite twists. Many of her novels and short stories had the murderer turn out to be a man and a woman in a Secret Relationship who either pretended to dislike each other or not know each other, and then use that to create alibis and opportunities for each other.
  • She first used it in her very first novel, The Mysterious Affair at Styles. Alfred Inglethorp and Evelyn Howard pretend to hate each other, but they are secretly in cahoots to kill Emily Inglethorp (Alfred's wife and Evelyn's boss).
  • They Do It With Mirrors: Lewis and Edgar—secretly father and son—collaborated on the murder, with Edgar Holding Both Sides of the Conversation while Lewis stole off to do the deed.
  • Evil Under the Sun: Supposedly Christine and Patrick are in a dysfunctional marriage and Patrick is carrying on an affair with Arlena, who turns up as the murder victim. In fact Christine and Patrick are quite Happily Married, and evil, as they collaborated together to kill Arlena.
  • Death on the Nile: Linnet and Simon are a honeymooning couple, with Jaqueline the Woman Scorned stalking them. It turns out that Simon and Jacqueline were in cahoots from the beginning to kill Linnet so that they'd get their hands on her money.
  • Third Girl: Andrew Resnick and his wife Mary conspired to kill Andrew's old girlfriend Louise, because "Andrew Resnick" is actually an impostor and the real Andrew's old lover from back in the day, Louise, is basically the only person alive who can identify him as a fake.
  • Dead Man's Folly: George and Hattie, a married couple, conspired to kill multiple, people, including the real Hattie (George's wife is an impostor), and two other people who knew of their crime.
  • The Murder at the Vicarage: Anne Protheroe and Lawrence Redding separately confess to the murder of Anne's husband in order to paint themselves as a pair of Star-Crossed Lovers, when in truth they carefully planned the crime together so that both would have an airtight alibi and be cleared as suspects.

Individual works:

• The Cat in the Stacks Mysteries:
  • In book 2, it turns out that the two major crimes (the murders of James Delacorte and Eloise Morris, and the theft of some of Delacorte's rare book collection) were committed by different people. The killer, Nigel Truesdale, did so to speed up his inheritance. The thief, Delacorte's nephew Hubert, stole part of his uncle's rare book collection to pay for pretty things for his mistress.
  • In book 3, after the initial murder of Conner Lawton, there are further crimes committed: Charlie's daughter Laura is hit from behind in her office at work, someone tries to burn down the house, Damitra Vane is found dead with her throat cut, and a letter bomb is sent addressed to Laura. It turns out that Sarabeth Conley (née Norris) had killed Conner via suffocation because his play was going to expose her earlier murder by drowning of her father, more than thirty years ago, but the other attacks were carried out by her son Levi. Sarabeth, who was unaware of any of these attacks until Charlie and Laura mentioned them, was horrified when she realized what he'd done.
  • In book 9, the cold case Charlie is working on — the murders of four people, twenty years ago — turns out to have been this. Hiram Barber murdered his wife and her sons by her lover after discovering their true parentage, and then his daughter Elizabeth shot him in the back when she realized what he'd done.
  • In book 10, the two main crimes — the murder of Gerry Albritton, and the embezzling of funds from her business partner — were committed by two people, as revealed in the last chapter. Gerry was killed by her own sister, Betty Camden, while the embezzling was done by her assistant, Jincy Bruce. A third crime, the sabotage of Gerry's Christmas decorations, turns out to be the doing of yet another person: Gerry's brother Billy Albritton, who was trying to scare her out of the neighborhood.
  • In book 12, Luke Lombardi is the target of multiple pranks, starting with being delivered a set of pigs' ears as a "special treat" at a reception, then finding a dead snake in his dressing room and finally having his tea spiked with hot peppers. Later though, he's murdered when someone sneaks cyanide into his drink during the actual performance. During a reenactment of the performance, his understudy Jared Eckworth confesses to being behind the snake and the pepper, and was planning to do it a second time so he could perform in Lombardi's place, but didn't get the chance. The actual killer, however, is Anton du Jardin, who'd taken an insurance policy out on Lombardi and wanted to cash it in.
  • Turns out to be the case in book 13 — Elmore Gregory decided to kill Denis Kilbride after learning his wife had tried to do so because of Denis's role in her son Todd's suicide, but couldn't bring herself to actually do it. Burdine is later overcome with rage and murders Cora Apfel after Cora stole a brooch that the late Todd Gregory had given her, and also poisons Zac Ryan after seeing him flirting with men like Denis had.
  • Discussed in book 15, where Charlie suspects that the murderous attacks on Wil Threadgill and his bandmates (both current and former) are completely unrelated to the other crime that's been discovered (Wil's manager and personal assistant Chelsea embezzling from him). He's right, as it turns out the killer, who tried to get to Chelsea to kill her but couldn't before she committed suicide, is actually the first victim's daughter.
• Dark Places: There are two killers working separately. One is Calvin Diehl, "the Angel of Debt", who Patty hired to kill her, and ended up killing Debby accidentally. The other killer is Diondra, working completely separately, who kills Michelle because Michelle learned about her pregnancy.
• Discworld: In Maskerade, the major break in the case happens when Granny realizes there are two Opera Ghosts. One Opera Ghost is the hapless but good Walter Plinge, who used the Ghost to hide out under the opera house and do some other mysterious but not evil things. The other is Salzella and actually killed the dead opera members.
• Forest Kingdom: Used more than once in the Hawk & Fisher spinoff series.
  • In book 1, a werewolf proves responsible for most of the murders due to being trapped in a house full of potential victims during the full moon, but Adam Stalker, a member of the influential DeFerrier family who was operating under an alias was responsible for the deaths of Councilor William Blackstone and later his wife Katherine.
  • In book 2 (Winner Takes All), early on, James Adamant tells Hawk and Fisher that someone's been embezzling from him, and leaking information on his campaign to his enemies. It's revealed later that two different people were responsible — his political advisor had fallen for a woman who was working for the opposition and was being tricked into telling her all sorts of things, while Adamant's wife Dannielle was embezzling to feed her drug habit.
• Hive Mind (2016): In Hurricane, the pranks at the Sea Farm were initially committed by Treeve, who then went to the mine for a while and told Massen, who had already been cleared by Morton, to commit some more so that he'd have an alibi. The murders were committed by a third person, Treeve's daughter Rose.
• In The Illuminatus! Trilogy universe, John F. Kennedy was shot by five snipers simultaneously.
• This is one of the theories floated in the Jesse Stone novel and TV movie Stone Cold, based on the fact that the bullets recovered from the victims came from two different guns. Turns out there's "one shooter, two guns," but she was helped by her husband.
• Judge Dee: After a retired general is found dead the day after his birthday, with clues pointing at a local painter (whose father claimed the general was a traitor and a coward, and was kicked out of the army for it), the Judge investigates and discovers a tiny arrowhead embedded in the general's throat, along with poisoned fruit. It turns out the general was wanted dead by two people: a (now-dead) former governor who knew the general was a traitor^note he'd bribed an enemy into retreating by sacrificing part of his army- the part Tsiao Tai was in, and the general's son, who was having an affair with one of his father's concubines, a major no-no in Tang society (it's outright referred to as incest). The son gave his father a box of poisoned fruit, hoping to blame the murder on the painter, while the governor had given the general a booby-trapped quill, to be used on the day he wrote his memoirs. The quill killed the general, but the Judge orders the general's son to commit suicide (see major no-no above).
• A Line to Kill: Middle-aged author Anne Cleary and Sexy Secretary Kathryn Harris are revealed to be mother and daughter. They worked together to lure Asshole Victim Charles le Mesurier away from a party, so they could kill him, because they blame him for the death of Anne's son and Kathryn's brother.
• Retired Witches Mysteries:
  • During the events of book 1, the coven learns that two people are responsible for the death of Olivia and the theft of their spell book — a witch, and a thief who does their bidding. The thief and killer turns out to be Lisbet, Joe's partner as a homicide detective, under the influence of her mother Matilda, an ancient witch who's trying to extend her own life by killing other witches and stealing their powers.
  • In book 3, Makaleigh Verza, a member of the Grand Council of Witches, is murdered. Hedyle, her arch-rival, set it up and got another member, Bairne Caelius, to do the actual killing, because Makaleigh wanted to make changes to the council that Hedyle and Bairne didn't approve of. Shortly after it comes out, Hedyle herself is killed, but it turns out to be the witchfinder Antonio de Santiago, who was just taking advantage of the confusion and knew her death would free him.
• In Wings of Fire, Tsunami initially assumes that the dragon killing Queen Coral's unhatched daughters is the same one who tried to kill her, herself a daughter of Coral. It turns out, however, that the killer of her sisters is an enchanted statue created by Orca, while Whirlpool was the one who tried to kill her.

• American Vandal:
  • The main characters wonder about the possibility in season one that more than one person was responsible for vandalizing the teachers' cars. Near the ending, they come to the conclusion that the most likely culprit, Christa, worked together with her boyfriend to do it, since she had her leg broken at the time. While she deleted the footage of the crime, her boyfriend did it.
  • Season 2 plays with this. It turns out that the pranks were the work of many people, the actual criminal blackmailed all of them to force them into playing the pranks for him.
• Castle:
  • The detective squad catches two separate murders on the same night but keep running into dead ends, until Lainie discovers that the two victims have the same traces of diatoms on them and realizes they're connected. Beckett and Castle decide to swap cases with Ryan and Esposito to get fresh eyes on it... and Castle has a "Eureka!" Moment that this is exactly what the killers did: they each killed the other's intended victim to confuse the cops and get an alibi for the murder they actually wanted committed.
  • Castle competes with Beckett's Romantic False Lead over who can solve the murder first, with each man focusing on one particular suspect. Beckett's the one who realizes that both suspects did it. They weren't working together, and had no idea the other one had done anything, they just both wanted the guy dead. Esposito tells Beckett it was generous of her to let both the guys win.
• Columbo: This is the final reveal of Double Shock. The episode shook up the normal Columbo formula by showing the murder as normal and then a bit later revealing the murderer is one of a pair of identical twins, leaving the viewer uncertain which of the two did it. As the presence on this page indicates, it turns out they worked together on the murder.
• Criminologist Himura and Mystery Writer Arisugawa:
  • The victim of "A Study in Vermilion - Part 2" was bludgeoned over the head and then, a little later, had a rock dropped on her from a high place. Initially thought to be a single suspect making sure she was dead, it soon becomes clear that two people are involved.
  • In "ABC Killer", the four murders are revealed to have been committed by two different people. The first two victims were killed by the third victim. The third and fourth victim were then killed by the main suspect of the case, leaving her with an alibi for two of the supposed serial killer victims.
• The Blue Paint Killer in CSI. The first ep has the believed killer escaping execution due to more bodies being found, then he dies at the end. In the later ep, more cases popped up, and the group realized the executed man was just the apprentice. The guy captured in that episode was the real main killer. Both men did the crimes, though.
• In Death in Paradise, this turns out to be the solutions in "The Blood Red Sea", "The Complex Murder", and "Murder at the Polls".
• Law & Order:
  • In the episode "Blood Money", two different assassins catch up with the victim-of-the-week at the same time, resulting in him getting shot by one killer, then stabbed by the second, so close together that the victim is still alive after the bullet wound when he's stabbed. DA Jack McCoy has a bit of trouble figuring out how to prosecute both suspects for murder when only one victim died.
  • A much creepier case occurs in "Harvest": a woman sustains life-threatening injuries, including a traumatic brain injury, in a street shooting, and eventually dies in the hospital. The police arrest the shooter and he's charged with murder. However, pre-trial investigation discovers that while the woman's death was ultimately due to the bullet wounds, it may have been directly caused by her doctor, who lied and falsified records to show she was brain-dead so he could harvest her organs for transplant.
• This trope is rare in Midsomer Murders, but it does happen in "The Creeper", where the killers turn out to be a mother and daughter-in-law killing to protect a family secret.
  • In "A Tale of Two Hamlets", the first two murders were committed by Danny Pinchel and Phil Harrison working in concert. The third murder was Phil Harrison disposing of his partner-in-crime.
  • In "Claws Out", Madeline Saunders emotionally blackmails Perry Fleming into committing the first two murders for her, then commits the third one herself.
  • In Blood Will Out Hector Bridges was killed by his stepdaughter Fleur in arguable self-defence. John Smith was killed by Will Saxby (Fleur's father) when he broke into John Smith's caravan as part of a scheme to lead the police away from Fleur and unexpectedly found John napping.
• Psych: In season 3, Shawn captured serial killer Mr. Yang. It isn't until a year later that it was revealed that she had a partner, Mr. Yin (Mary was killed after figuring this out). A year after that, it was revealed that Yin was Yang's father, and, though they worked together, he was actually the one who committed the murders.
• Return to Paradise: In "Curl Up and Dye", the murder is committed by two of the salon employees: Skye strangled her sister Bianca, while Tahnee sold the illusion that Skye was somewhere else, thus establishing an alibi.
  • "Apex Predator", Asher and Susie conspire to murder Brian. Susie commits the actual murder, while Asher establishes the impression of Brian being elsewhere, allowing both of them to appear to have an alibi for the time of the murder.
• Like the movie it's based on, the killer in the first season of Scream: The TV Series turns out to have been two people. This is first suspected by the characters when the killer of the first season is revealed, as they were seemingly attacked by the killer in a previous episode. The surviving killer then becomes the new Big Bad of the next season, their motive being revenge for the death of their accomplice.
• An episode of Supernatural had the Winchesters investigate murders they assumed had been committed by a ghost or some other supernatural creature due to its apparent ability to teleport, but turned out to be the actions of two normal guys pretending to be some kind of ghost.
• Veronica Mars: This is the solution to the Hearst College Rapist plot in season 3: Mercer and Moe worked in tandem to commit the crimes. Mercer, The Charmer with some criminal connections (the fact that he ran an Illegal Gambling Den out of his dorm was a minor plot point earlier in the season) that enabled him to procure date-rape drugs, would attend frat parties to scout potential victims and Slip them a Mickey. Moe, a Residence Advisor and volunteer driver for Take Back the Night^note A student organization that sought to curb on-campus sexual assaults by providing a safe escort for women from campus locations, such as frat parties, to their dorms; it should be noted that there's a certain amount of Artistic License at play, since real-life organizations of this kind typically have escorts work in pairs, and usually mixed-gender pairs, to prevent exactly this from happening, would escort them back to their dorms and inform Mercer, who would leave the party and do the deed; since he ran a late-night music program on the College Radio station, leaving early wouldn't be seen as suspicious, and since few people knew he could run the show from his laptop (or that he occasionally pre-recorded it, the show is unclear on this point), he had a perfect Fake Alibi. Investigators have no reason to suspect the pair are working together, because they don't have overlapping social circles, except coincidentally due to Moe being an RA; Veronica only figures it out after she realizes they were previously both enrolled in the same criminology class she's taking, and which runs a Stanford Prison Experiment every year, which is where the two met and developed a very unhealthy dynamic.

• Curtains: While Daryl Grady murdered Jessica and Johnny and attempted to kill Carmen and Cioffi, it turns out he didn't murder Sid, as Grady's entire motive for the murders was to ensure Robbin' Hood never made it to Broadway, which Sid agreed with Grady to do in exchange for glowing reviews of his next three shows. Cioffi deduces that it was Carmen who murdered Sid to ensure that the show would stay open and Bambi's career wouldn't suffer.

• In Kathy Rain 2: Soothsayer, One of the main reveals about the titular Serial Killer that, whereas the police assumed there was only one perpetrator behind the killing, due to the Calling Card left at the crime scenes, they were actually orchestrated by two different killers working somewhat loosely together, explaining why there seemingly was no discernable pattern in choice of victim and murder method. When looking at their killings separately, however, the pattern becomes quite a bit more clear: Wiktor Kopernik, due to his Mommy Issues and being The Brute of the pair, targeted middle-aged women and brutally stabbed them to death; Faith Cyrene, having more of a flair for the theatrical, chose to play a Poetic Serial Killer and targeted mentally vulnerable people and manipulated them into committing suicide.
• In Knights of the Old Republic, the Jedi council asks you to investigate a murder with two suspects, each accusing the other. Turns out they both did it, but not intentionally, they just happened to act on their separate plans simultaneously. Then it turns out to have been a Secret Test of Character — the Jedi master "assisting" your investigation had already solved it on his own.
• In Paradise Killer: The full investigation eventually reveals that there were two separate plots to murder the Council that happened on the same night, completely unaware of each other. The player can unveil both, or play favorites to spare characters they sympathize with.
• In Persona 4, there are actually three. One copycat, one pawn who thought he was defeating the killer (while actually creating new victims) and then the original killer that orchestrated the whole scheme. There's also a Man Behind the Man, who had nothing to do with the killings but caused them indirectly by empowering the original killer and the pawn.
• In the This War of Mine DLC Father's Promise, the burglary in the Pharmacy was committed by two separate parties. The perpetrator who left the only trail is not the perpetrator who left the clues to your Driving Question; it is sheer coincidence that following the first perpetrator's trail allows you to pick up the trail of the second.

• Ace Attorney:
  • Phoenix Wright: Ace Attorney – Trials and Tribulations has between one and four antagonists for the final case, depending on how you look at it.
  • Ace Attorney Investigations: Miles Edgeworth:
    • The first case features Edgeworth investigating a theft and murder that occurred in his office, having been threatened by the culprit as they made their escape. He eventually deduces that the two crimes were committed by different people, which helps to discredit a suspect's alibi for when the theft took place.
    • There's also the Yatagarasu, a Phantom Thief who pulls off seemingly impossible heists in order to expose corruption and dirty dealings. The Yatagarasu's secret is that it's made up of three different people: a defense attorney who scoped out the targets under the guise of representing them, a prosecutor who committed the actual thefts, and a detective who concealed the evidence during the investigation.
  • Phoenix Wright: Ace Attorney – Dual Destinies: The first case opens with a detective allegedly having been killed during a courtroom bombing. Phoenix eventually proves that the victim was bludgeoned to death with the bomb itself, which the killer detonated afterward to get rid of the evidence of his crime. It isn't until later that the full truth comes out: the bomb was actually set off by a third party with a completely different motive, and the detective's killer went along with it because it suited his agenda.
  • Phoenix Wright: Ace Attorney – Spirit of Justice:
    • Case 1 has a young boy being put on trial for the theft of a national treasure and the murder of a security guard in the temple where it was held. The truth is much more complicated: the guard had attempted to steal the treasure himself, but he realized someone else had already stolen it due to the treasure box being lighter than it was supposed to be. He decided to steal the box anyway, only to be bludgeoned to death by the temple's head monk when he stopped to interrogate the defendant about the treasure's disappearance. The head monk had helped smuggle the treasure out of the country, and being the only one who knew how to open the treasure box, he had to kill the guard and frame the defendant to cover up the disappearance.
    • Case 3 has two victims of an alleged serial killer who actually died from separate causes. One was a killing committed in self-defense, which due to Khura'in's legal system would never stand as a defense in court. Therefore, the husband of the first "killer" killed himself in order to frame an innocent third party for both crimes, ensuring his wife would escape suspicion in the first killing.
• Danganronpa does this a lot; aside from the fact that Monokuma is the Big Bad responsible for every murder as the host of the Mutual Killing Games, nearly every case has at least two culprits, though usually with one being the central planner and murderer.
  • Danganronpa: Trigger Happy Havoc:
    • Chapter 1: Leon was the one who killed Sayaka, but she tried to kill him first, only for him to fight back and kill her instead. The manga also has it be an Accidental Murder on Leon's part.
    • Chapter 2: Mondo murdered Chihiro, but Byakuya tampered with the evidence to blame it on and draw out Genocide Jack, the Serial Killer hiding among them.
    • Chapter 3: Celeste trucked Hifumi into killing Kiyotaka, then killed Hifumi herself to keep him from talking.
    • Chapter 4: Sakura was Driven to Suicide, but Aoi was manipulated by a fake suicide note written by Monokuma into trying to get everyone else killed as well.
    • Chapter 5 and 6: Eventually, it's revealed that there are two masterminds behind Monokuma, collectively known as the Ultimate Despair. However the mastermind who was manually controlling the bear, Junko Enoshima, murdered her accomplice Mukuro Ikusaba early in the story by baiting her into breaking the rules. This was done to hide the fact that they had swapped identities.
  • Danganronpa 2: Goodbye Despair:
    • Chapter 1: Teruteru killed the Ultimate Imposter, but Nagito goaded him into it in the first place. Teruteru was actually aiming for Nagito.
    • Chapter 2: Subverted. Peko killed Mahiru, but it seems that Fuyuhiko ordered her to do it. Turns out Peko did it of her own accord, assuming Fuyuhiko would order her to do it.
    • Chapter 3: Also subverted. It seems that Hiyoko may have been an accomplice to the murder of Ibuki, but she was not; Mikan killed both of them on her own.
    • Chapter 4: Gundham killed Nekomaru, but they fought in a Duel to the Death. Had Nekomaru won, he would have killed Gundham.
    • Chapter 5: Chiaki was the direct killer of Nagito, but Nagito himself set things up so she would accidentally kill him.
    • Chapter 6: There are in fact two-to-three masterminds: Nagito, who manipulated the other students and set up much of the conflict; Monokuma/Junko, the host of the killing game; and Izuru Kamukura, Hajime Hinata's Superpowered Evil Side who put the Junko AI into the Neo World Program.
  • Danganronpa Another Episode: Ultra Despair Girls: The war between kids and adults in Towa City was set up by Monaca Towa and AI Junko Enoshima, the latter disguised as Shirokuma and Kurokuma.
  • Danganronpa 3 Side:Future: The mastermind of the Final Killing Game is Kazuo Tengan, head of the Future Foundation, whose goal was to eradicate despair for good by tormenting Ryota Mitarai until he snapped and decided to use his talent to brainwash the entire world into feeling nothing but hope. The "spy" that was supposedly going around killing everyone does not exist, all of the "murders" were actually brainwashing-induced suicides. Monaca Towa also killed Miaya Gekkogahara at some point before the events of the killing game and replaced her with a remote-controlled robotic duplicate that she was using to spy on the Future Foundation, but she was ultimately a Red Herring who had nothing to do with the Final Killing Game.
  • Danganronpa V3: Killing Harmony:
    • Chapter 1: Kaede set up a trap to kill the mastermind, but ended up accidentally killing Rantaro with it instead. Except she didn't, the trap missed. The mastermind, Tsumugi, then killed Rantaro herself and arranged the scene to make it look like the trap worked to keep the killing game on-script.
    • Chapter 2: Actually averted; Kirumi is the sole culprit behind Ryoma's murder this time. Although Ryoma did let himself get killed because he discovered he genuinely had nothing to live for and no one waiting for him on the outside.
    • Chapter 3: Subverted; while it seems like Angie and Tenko may have been killed by two different people, Korekiyo murdered both of them. Of course, Korekiyo is two different people, or at least he thinks he is.
    • Chapter 4: Miu, the victim, was trying to kill Kokichi, only for him to manipulate Gonta into killing her.
    • Chapter 5: Kaito killed Kokichi, but at his request as part of a Thanatos Gambit.
    • Chapter 6: Tsumugi is the mastermind of the current killing game, but she's just one of many employees of Team Danganronpa, the true mastermind who makes the Danganronpa-themed reality show. And of course, the only reason they keep making the show is because the fans keep watching it and demanding more.
• The Great Ace Attorney:
  • Retroactively applied to Case 1 of the first game, as while Jezail Brett is the killer, we find out at the end of the second game that Seishiro Jigoku, the judge of Case 1, was the one who ordered the hit on the victim.
  • In Case 2 of the first game, Nikolina Pavlova was the crime's accidental culprit, while Bif Strogenov worked with her to cover it up.
  • Both Enoch Drebber and Courtney Sithe were responsible for Case 3's murder in the second game. Drebber set up most of the crime, while Courtney physically killed the victim and assisted Drebber.
  • Cases 4 and 5 of the second game have two sets of these. In the present, Seishiro Jigoku was Gregson's murderer, but Mael Stronghart was the mastermind behind it, and the events of both games. In the past, Klint van Zeiks was the Serial Killer known as The Professor, but was killed by Genshin Asogi in a duel once he found out, and Genshin was scapegoated for all the murders.
• In Nine Hours, Nine Persons, Nine Doors, the True Ending of the game reveals that the mastermind behind the Nonary Game, Zero, is actually two of the game's participants. Though Santa is actually The Dragon to Zero/Akane. Also, Ace masterminded the first Nonary Game and is the reason Akane did this one.
• One of the endgame reveals in Spirit Hunter: Death Mark II is that both of the recurring schoolgirl characters, Himeko Douryou and Michiho Kinukawa (or at the very least, facsimiles of them), are the Departed that had kickstarted the spirits' reign of terror in Konoehara Academy to begin with, and picking both of them as the Departed in Kazuo's final deduction is the key to avoid getting the bad ending.
• A possible theory about the truth of the Rokkenjima Mansion massacre in Umineko: When They Cry is that the events are caused by two teams working independent of each other, one planning and one opportunistic. It eventually turns out that this is indeed the case — Beatrice/Yasu was the one who planned the Deadly Game, but when everyone won and lived, it was Kyrie and Rudolf Ushiromiya who shot and killed everyone (except Eva, who killed back in self-defense) so they could get the Rokkenjima treasure.

• xkcd has a cartoon proposing a parodic compromise with the 9/11 "truthers": One of the twin towers was destroyed by a secret US government conspiracy and made to look like an Islamic terrorist attack... and the other tower actually was destroyed by Islamic terrorists. Both attacks happened on the same day by complete coincidence.

• The Painter: One of the early plot twists is that there are two serial killers working together in tandem.

• Central Park: In Season 3 "A Matter of Life and Boeuf", someone stole Ambrose's cote de boeuf (an expensive steak) and later on they discover someone added poison to the steak with the intent to kill Ambrose. It turns out Kendra added the steak sauce to kill Ambrose so she can inherit his money, but didn't account for Anton stealing the steak to sell on the black market. They were going to use the money to start a new life together.

• The Hillside Strangler turned out to be the Hillside Stranglers, Angelo Buono and his cousin Kenneth Bianchi. The police in that case had actually guessed beforehand that they might be dealing with two killers, thinking that two men would have an easier time carrying and dumping bodies around Los Angeles suburbs.