A "whodunit" is a form of mystery, which presents a crime and then challenges the reader to solve it. The story's protagonist -- often a professional or amateur detective -- serves as the readers' surrogate: asking questions until the criminal and the methods he used finally come to light. There are countless whodunit short stories, filling the ranks of literary libraries and pulp fiction alike. The very best of them form the touchstones for the entire genre.
"The Murders in the Rue Morgue"
Edgar Allan Poe wrote "The Murders in the Rue Morgue" in 1841, marking the first appearance of the detective story in the annals of literature. It introduced Poe's detective Dupin, who himself became the model for similar detectives like Hercule Poirot. In the story, Dupin investigates a murder which takes place in a locked room with no apparent exits. He eventually determines that a trained orangutan committed the murder, then escaped by scaling the wall of the room and climbing out a window.
Sherlock Holmes -- the creation of author Arthur Conan Doyle -- remains the most famous whodunit protagonist in the world. Doyle published several dozen Holmes short stories -- mostly in the pages of Strand Magazine -- during the 1890s and 1900s. Each one presented a baffling mystery with no apparent motivation, which the arrogant but brilliant Holmes would solve. Holmes's colleague Dr. John Watson, served as the stories' narrator and chronicler of Holmes' adventures. The stories include "A Scandal in Bohemia," "The Adventure of the Speckled Band" and "The Adventure of the Red-Headed League."
Hammett and Chandler
The years before World War II saw a new form of whodunit story emerge, featuring a new kind of detective. They were hard-boiled, street smart, tough, cynical and possessing a rough code of working man's honor: a far cry from refined detectives like Holmes and Dupin. They appeared in the pages of mystery magazines like Ellery Queen and Black Mask. Chief among their architects were Dashiell Hammett and Raymond Chandler, who perfected the "hard boiled" detective story. Their tales include titles like "The King in Yellow," "The Curtain" and "The Big Knockover," as well as longer novels like "The Glass Key" and "Farewell, My Lovely."
"Yours Truly, Jack the Ripper"
The standard set by Chandler and Hammett continued into the second half of the 20th century, with numerous other writers taking up their mantle. The best of them expanded the whodunit story in new and fresher directions, incorporating elements of horror, comedy and other genres to set them apart. "Your Truly, Jack the Ripper" is a key early example, written by author Robert Bloch (who later penned the novel "Psycho"). It concerns an Englishman who believes that the Ripper is still alive in the 20th century, and committing murders in order to unnaturally sustain his life. In the end, the Englishman's trusted confidante (and the story's narrator) is revealed as the Ripper.