Film noir is a film genre sharing its setting with gangster film, police procedural, gothic romance, and social problem films, with the typical protagonist being - as in the Noir fiction - either a victim, a suspect, or a perpetrator, dealing with the legal, political or other system that is seen as corrupt; the stories written by hardboiled writers in the early 1940s, describing the atmosphere during the Prohibition-period in America, were adapted for the screen by the Austro-German[a] film-making emigrants in Hollywood who fled the similarly corrupt system in Europe which allowed for the Nazi movement to gain the power. It is visually associated with a low-key black-and-white visual style that has roots in German Expressionist film. (x)