Inverted detective story

An inverted detective story, also known as a "howcatchem", is a murder mystery fiction structure in which the commission of the crime is shown or described at the beginning, usually including the identity of the perpetrator. The story then describes the detective's attempt to solve the mystery. There may also be subsidiary puzzles, such as why the crime was committed, but those are cleared up along the way. This format is the opposite of the more typical "whodunit", where all of the details of the perpetrator of the crime are not revealed until the story's climax.

R. Austin Freeman claimed to have created the inverted detective story in his 1912 collection of short stories The Singing Bone.

Some years ago I devised, as an experiment, an inverted detective story in two parts. The first part was a minute and detailed description of a crime, setting forth the antecedents, motives, and all attendant circumstances. The reader had seen the crime committed, knew all about the criminal, and was in possession of all the facts. It would have seemed that there was nothing left to tell. But I calculated that the reader would be so occupied with the crime that he would overlook the evidence. And so it turned out. The second part, which described the investigation of the crime, had to most readers the effect of new matter.

One early and prominent example of this subgenre is Malice Aforethought, written in 1931 by Anthony Berkeley Cox writing as Francis Iles. Freeman Wills Crofts's The 12:30 from Croydon is another important instance.

The 1952 BBC television play Dial M for Murder by Frederick Knott (later adapted for the stage and then adapted again in 1954 as a theatrical film by Alfred Hitchcock) is another example. Tony Wendice outlines his plans to murder his wife Margot in the opening scenes, leaving the viewer with no questions about perpetrator or motive, only with how the situation will be resolved. In Alfred Bester's 1953 novel, The Demolished Man, the reader learns in the first chapter that Ben Reich plans to murder a man; the rest of the novel is concerned with whether he will get away with it.

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