Definition and characteristics
Mystery films mainly focus with solving a crime or a puzzle. The mystery generally revolves around a murder which must then be solved by policemen, private detectives, or amateur sleuths. The viewer is presented with a series of likely suspects, some of whom are "red herrings," –persons who have motive to commit the crime but did not actually do it–, and attempts to solve the puzzle along with the investigator. At times the viewer is presented with information not available to the main character. The central character usually explores the unsolved crime, unmasks the perpetrator, and puts an end to the effects of the villainy.
The successful mystery film adheres to one of two story types, known as Open and Closed. The Closed (or whodunit) mystery conceals the identity of the perpetrator until late in the story, adding an element of suspense during the apprehension of the suspect, as the audience is never quite sure who it is. The Open mystery, in contrast, reveals the identity of the perpetrator at the top of the story, showcasing the "perfect crime" which the audience then watches the protagonist unravel, usually at the very end of the story, akin to the unveiling scenes in the Closed style.
Mystery novels have proven to be a good medium for translation into film. The sleuth often forms a strong leading character, and the plots can include elements of drama, suspense, character development, uncertainty and surprise twists. The locales of the mystery tale are often of a mundane variety, requiring little in the way of expensive special effects. Successful mystery writers can produce a series of books based on the same sleuth character, providing rich material for sequels.
Until at least the 1980s, women in mystery films have often served a dual role, providing a relationship with the detective and frequently playing the part of woman-in-peril. The women in these films are often resourceful individuals, being self-reliant, determined and as often duplicitous. They can provide the triggers for the events that follow, or serve as an element of suspense as helpless victims.