Whodunnit

A whodunit or whodunnit (for "Who [has] done it?" or "Who did it?") is a complex, plot-driven variety of the detective story in which the audience is given the opportunity to engage in the same process of deduction as the protagonist throughout the investigation of a crime. The reader or viewer is provided with the clues from which the identity of the perpetrator may be deduced before the story provides the revelation itself at its climax. The investigation is usually conducted by an eccentric, amateur, or semi-professional detective.

Journalist Wolfe Kaufman claimed that he coined the word "whodunit" around 1935 while working for Variety magazine. However, an editor of the magazine, Abel Green, attributed it to his predecessor, Sime Silverman. The earliest appearance of the word "whodunit" in Variety occurs in the edition of August 28, 1934, in reference to a film adaptation of the play Recipe for Murder, as featured in the headline, "U's Whodunit: Universal is shooting 'Recipe for Murder,' Arnold Ridley's play". The film was eventually titled Blind Justice.

The "whodunit" flourished during the so-called "Golden Age" of detective fiction, between 1920 and 1950, when it was the predominant mode of crime writing. Many of the best-known writers of whodunits in this period were British — notably Agatha Christie, Nicholas Blake, G. K. Chesterton, Christianna Brand, Edmund Crispin, Michael Innes, Dorothy L. Sayers, Gladys Mitchell, and Josephine Tey. Others – S. S. Van Dine, John Dickson Carr, and Ellery Queen — were American, but imitated the "English" style. Still others, such as Rex Stout, Clayton Rawson, and Earl Derr Biggers, attempted a more "American" style.

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