Film Noir
Film Noir  (literally 'black film or cinema') was coined by French
film critics (first by Nino Frank in 1946) who noticed the trend of
how 'dark', downbeat and black the looks and themes were of
many American crime and detective films released in France to
theatres following the war

Film Noir is the flip side of the all-American success story. It's
about people who realize that following the program will never
get them what they crave. So they cross the line, commit a crime
and reap the consequences. Or, they're tales about seemingly
innocent people tortured by paranoia and ass-kicked by Fate.
Either way, they depict a world that's merciless and unforgiving.

Film Noir is a sub-genre of crime films that developed in the
United States during World War II that featured people acting out
of desparation in a bleak and morally ambiguous world. They were
made in black and white, and had a dark, high-contrast,
expressionistic visual style. Film Noir is primarily based on the
hard-boiled crime fiction of the thirties (many Films Noir were
adaptations of those novels) and the dark gangster films of the
thirties.