Who Dunnit to Me?

"Frank Bigelow: I'd like to report a murder. Captain: Sit down. Where was this murder committed? Frank Bigelow: San Francisco, last night. Captain: Who was murdered? Frank Bigelow: I was."

- D.O.A.

This is where the protagonist has been murdered and is either dead or soon will be. The rest of the story concerns their efforts to solve the crime in the time they have left. A subplot can also be their trying to protect a loved one from the killer who did them in. This can be supernatural or non-supernatural depending on whether the protagonist is already dead or dying slowly but inevitably. If he or she is already dead, may involve Near-Death Clairvoyance, otherwise may be considered a form of Death by Origin Story.

A common science-fictional version involves characters who have the ability to back themselves up, through Brain Uploading or some similar technology. This is often used as a way to get around the issue that most victims know who murdered them: the version of the character that's trying to solve the murder is only as up-to-date as their most recent backup, which means they naturally have no memory of the murder or anything immediately before it.

Anime and Manga

 * Lia in Le Chevalier d'Eon, who possesses her living younger brother to find out who murdered her.

Comic Books

 * The Shade the Changing Man story arc 'The Road' becomes an inverse murder mystery.
 * This was the whole idea behind the DC Comics character Deadman, who died in his first story - and became a superhero as a result, fighting crime in spirit-form while investigating his own death. At one point, it looked like his killer was the same thug who had murdered Batman's parents.
 * This was part of the title character's original motivation in Ghost from Dark Horse Comics.

Film

 * Ghost
 * The Crow
 * Treat Williams does this in Dead Heat. Note that he's a cop who was investigating the bad guys before he's killed; becoming a zombie just lets him see the case through till the end.
 * The '50s movie You Never Can Tell tells the story of a murdered dog who was sent back by 'dog heaven' as a human to investigate his own murder.
 * The movie Oh Heavenly Dog reverses this, sending back a murdered human in dog form to investigate his death.

Literature

 * Remember Me, a novel by Christopher Pike. Shari begins the novel already dead. She was killed at a party, and being a ghost she must figure out which one of her friends killed her.
 * The novel Never Trust A Dead Man pairs this with Clear My Name and Enemy Mine: the protagonist, Selwyn, is forced to cooperate with his murdered rival (who has been brought back from the dead in the form of a bat) to find the real murderer and clear Selwyn's name.
 * 9Tail Fox by Jon Courtenay Grimwood involves a police officer who was shot from behind and resurrected in another man's body by the Celestial Fox.
 * Ghost Story, Book 13 of The Dresden Files, has this as its plot, with a
 * James Herbert's Nobody True is told from the POV of a ghost seeking his killer ... who can astrally project to oppose him.
 * In Who Censored Roger Rabbit? (the novel from which the film Who Framed Roger Rabbit? was adapted), Roger is dead, and a doppleganger he created using his toon abilities hires Eddie Valiant to investigate his murder.

Live-Action TV

 * Torchwood: "Random Shoes". Eugene's ghost follows the Torchwood crew around as they investigate his death. He manages to appear briefly to his family before Ascending to a Higher Plane of Existence.
 * One episode of CSI has the corpses of murder victims talking about their murders (as the CSIs solve the cases).
 * The first episode of Randall and Hopkirk Deceased - original and remake.

Radio

 * Edith, in Season 6 of Old Harry's Game agrees to write Satan's biography in exchange for Satan investigating her murder.

Tabletop Games

 * Ratik Ubel, an NPC revenant from Ravenloft, has been acting out this trope for years. Normally a D&D revenant exists just long enough to eliminate its killer, but Ubel never saw his murderer's face and has been relentlessly pursuing one lead after another, seeking whichever of his (many) old enemies was responsible.

Video Games

 * Shadow of Destiny, although he's trying to reverse his death as well.
 * The Flash adventure game The Dead Case
 * The World Ends With You  By the end of game it becomes clear that
 * Sissel's motivation as the eponymous ghost in Ghost Trick: Phantom Detective is not only to find his killer, but to find out who he is in the first place.
 * The eponymous character of the PC game Ghost in The Sheet starts the game by getting run over by a bus. He's not quite satisfied with the "it was an accident" theory, but he has to put it on the back burner in favor of the job his new boss has given him. At the end it's revealed that.
 * Sonny, from the flash game series of the same name, died prior to first game's start. He cannot remember what happened to him or anything about his life prior death, and wonders who resurrected him and why.

Web Comics

 * Slightly Damned begins with Rhea already in purgatory, ready to be judged, with no idea how she got there. She got better, and there's only so many places that her killer can be...
 * {...} in Hanna Is Not a Boys Name has been dead for a while now, and recently been shown that he was murdered. He doesn't actively pursue his killer (he doesn't like to dwell on the past), but the point stands that {...} died, he came back and his killer is still presumably at large. He may not care whodunnit, but the readers and other cast members seem to.
 * Rachel-Rebecca the Third from DMFA was a law school student who got murdered. After getting reanimated, she got her own murderer convicted and went on to establish legal rights for The Undead.
 * Saturday Morning Breakfast Cereal once pointed out one of problems with vengeful ghosts.
 * In No Songs for The Dead, the main protagonist Hector wakes up to find himself undead and unable to remember anything about what happened to him or his identity. The story revolves more around Hector trying to figure out his past and why he is now back, than his death.

Film

 * D.O.A., both the 1950 original and the 1988 "remake".
 * Crank: Chelios doesn't need to figure out who poisoned him, as the culprit leaves him a gloating video that admits and even shows the act. Rather, he needs to track him down for revenge.

Literature

 * A story in Alfred Hitchcock's Mystery Magazine involving a man who is shot, and has a near death experience. While still in the hospital, he tries to figure out who did it, and does. There's one more dangerous surgery to be done to get the bullet out, and the story ends with him saying "I'm ready."
 * Partially subverted in G. K. Chesterton's short story The Resurrection of Father Brown. The titular priestly detective is supposedly murdered and is just about to be buried before he wakes up in his coffin. It turns out he was fed a poison which caused him to go into a coma almost resembling death. The remainder of the short story concerns Father Brown's efforts to discover who did this to him.
 * According to More Information Than You Require, ninth US president William Henry Harrison was given a slow-acting poison at his inauguration that would kill him in thirty days, and told he would be given the antidote if he could figure out who poisoned him. As the book puts it, "Harrison was a great Indian-killer, but not much of a sleuth".

Live-Action TV

 * NCIS:
 * "Dead Man Walking". Genre Savvy Tony makes a comparison by name to DOA.
 * Also when Tony gets pneumonic plague.
 * Homicide: Life on the Street, episode "Subway".
 * Starsky and Hutch, episode "A Coffin for Starsky".
 * An early CSI: Miami was about a woman who was poisoned with radioactive materials by a Corrupt Corporate Executive (or rather ) because she happened to be the lawyer working the joint lawsuit against their illegal dumping practices.
 * Used in CSI, when an attorney who'd been working with Sarah informs her that she won't be able to finish the case because the bullet lodged in her cranium from a previous crime has shifted inside the skull and will soon kill her. Subverted when, against all expectation, she survives the surgery to remove the bullet,
 * Truth in Television: Georgi Markov, Alexander Litvinenko
 * The latter apparently Ripped from the Headlines in Law and Order: Criminal Intent. Litvenenko is actually mentioned by name.
 * A similar, earlier case in which a fight between two Northern European naval personnel ended with one pinning the other with a piece of equipment that discharged a radioactive field, and firing. It was reported that prosecutors were faced with the difficulty of how to press charges, because a fatal dose was delivered, but murder charges could not be pressed because it would take years for the victim to die.
 * New Amsterdam
 * The Monk series finale:
 * The Mentalist: Code Red.

Video Games

 * The Flash game Sixty Seconds To Live. The title is fairly self-explanatory here.

Literature
"Beatrice: "Battler Ushiromiya, at this time, I will kill you. And right now, there is no one on the island other than you. The only one alive on this island is you. Nothing outside the island can interfere in any way. And of course, I am not you. However, I am here now and will kill you." Battler: "Like a souped up version of the mystery with Doctor Nanjo's murder...... .........So......?" Beatrice: ".........Who...aaam I...?""
 * Who Censored Roger Rabbit? (Literature). Unlike Who Framed Roger Rabbit, Roger is dead, and his doppelganger (a temporary copy of himself) goes to Eddie to find out who iced the original.
 * Down and Out in the Magic Kingdom
 * Umineko no Naku Koro ni
 * Drawn to an epic Mind Screw at the end of Umineko Ep4 with this gem:


 * Especially since it is said in red (which means it must be true) and that he (and the reader) is supposed to figure who that person is.
 * The whole point of Higurashi no Naku Koro ni
 * To Live Again, novel by Robert Silverberg
 * Altered Carbon by Richard K. Morgan is a Film Noir style thriller, with an investigator hired by the restored backup of an apparent suicide. The victim does not believe that he could have possibly wanted to kill himself; indeed it would be futile given that he was backed up and brought back to life in under 48 hours and instead believes he was murdered and demands justice.

Live-Action TV

 * Pushing Daisies, in the pilot
 * In the Dollhouse episode "Haunted", Echo gets the personality of a recently dead woman who wants to solve her own murder.
 * Count Sessine from Feersum Endjinn by Iain M. Banks.
 * The cybrid Johnny from Hyperion.
 * The John Varley story, The Phantom of Kansas, opens with the protagonist awakening and discovering that this is the third time she's been restored from backup. The original, and the two previous backups, have all been killed.
 * Pextel in Stationery Voyagers wants justice on the drug runner who ran him off the road and required that he be mechanized. Laura Herrante, under the Crimson Owl protection, has buried herself on occasions. Fortunately for her, it's usually no mystery who killed her.

Tabletop Games

 * The Transhuman Space scenario "In The Walls", in the Cities on the Edge supplement, is about a "ghost" (uploaded intelligence) who was murdered but restored from backup. He's annoyed about that, but livid that the backup has been tampered with, meaning he has no memories of the past six months.