Detective fiction

Detective fiction is a branch of crime fiction that centres upon the investigation of a crime, usually murder, by a detective, either professional or amateur. It is closely related to mystery fiction but generally contains more of a puzzle element that must be solved, generally by a single protagonist, either male or female.

A common feature of detective fiction is an investigator who is unmarried, with some source of income other than a regular job, and who generally has some pleasing eccentricities or striking characteristics. He or she frequently has a less intelligent assistant, or foil, who is asked to make apparently irrelevant inquiries and acts as an audience surrogate for the explanation of the mystery at the end of the story.