|By jcstritt at clker.com|
These films were full of heavy shadows that enhanced the mystery, intrigue, and suspense of the story. The dimness and unclear camera angles camouflaged the action and kept the viewer guessing.
The stories sometimes had unreliable narrators. These were crime tales that unfolded through the villain or the detective. They used flashbacks a lot. The atmosphere was gloomy.
The non-linear plot-line was used in some film noir to baffle the viewer. This type of plot line has to be done very well to work in a movie and is more easily adapted to use in a novel.
The protagonist in this film genre is a male detective, or a guy outside of the social norm, someone tough and alienated. He is a hard-boiled dude.
There is a crime involved in the story that is either a murder, robbery, or suicide. Murder and robbery together are prominent in these tales.
Those are the basic characteristics of film noir.
A Comprehensive Encyclopedia of Film Noir: The Essential Reference Guide