Two Dun It
A type of reveal where misdeeds depicted in the work were in fact committed by two agents (man or beast), either separately or working together.
A less crowded version of Everybody Did It
. As this is a Plot Twist
trope, this page is Spoilered Rotten
Compare Lotsa People Try to Dun It
, where multiple characters make separate attempts on the life of the victim.
Anime & Manga
- 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.
- 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.
- When the killer crocodile is captured in Lake Placid, another one immediately appears.
- 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.)
- 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.
- Used in Hell Night. 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.
- 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.)
- 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.
- 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.
- 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.
- 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!"
- 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.
- In The Illuminatus! Trilogy universe, John F. Kennedy was shot by five snipers simultaneously.
- 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.
- 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 a poisoned fruit. It turns out the general was wanted dead by two people: a (now-dead) former governor who knew the general was a traitornote , 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).
- 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.
- 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.
- 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.
- 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.
- 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 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.
- Eventually it's revealed that there are two masterminds behind Monobear, the villain of Dangan Ronpa, collectively known as Super High-School Level Despair. There's a subversion, though: the mastermind who was manually controlling the bear murdered her accomplice early in the story, by baiting her into breaking the rules. This was done to hide the fact that they had swapped identities.
- A possible theory about the truth of Rokkenjima in Umineko: When They Cry is that the events are caused by two teams working independent of each other, one planning and one opportunistic.
- Phoenix Wright: Ace Attorney: Trials & Tribulations has between one and four antagonists for the final case of the original trilogy depending on how you count.
- In Ace Attorney Investigations: Miles Edgeworth, a contradiction arises from initially missing this in case one.
- Ace Attorney Investigations 2 has multiple "killers" in case one. The problem is figuring out (and proving) who did what and why.
- 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 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.