A type of reveal where misdeeds depicted in the work were in fact committed by two inviduals (man or beast), either separately or working together. A less crowded version of Everybody Did It. Being a Plot Twist trope, this page is Spoilered Rotten.
- 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, it turns out that there were two killers. This was also true in Scream 2, but by then it was expected. (However, Scream 3 and 4 have only one each.)
- Used in Hell Night. A bit 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.
- 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.
- 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 ep was the real main killer. Both men did the crimes, though.
- 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.
- 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.
- 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.
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