A whodunit or whodunnit (a colloquial elision of "Who [has] done it?") is a complex plot-driven variety of detective fiction in which the puzzle regarding who committed the crime is the main focus. The reader or viewer is provided with the clues to the case, 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. Source: Wikipedia (en)