Film noir got its origins in 30's detective stories, often called pulp fiction, gritty stories with sex, violence and seedy characters. Even the heros were often common people with street wisdom, often with a tough upbringing.
Soldiers returning from World War 2 and a cinematic audience that had survived the Great Depression demanded more adult films in theme, subject, and style. Wilder was impressed by author John Kain's pulp novella of "Double Indemnity", the same author of The Postman Always Rings Twice, but it was considered unfilmable due the the Hayes Code (of censorship). The script went through years of re-writes and applications before being allowed to be filmed in 1944. The Hayes Code first suppressed sex in films, then violence, later socialism, and was used to pass judgment on over 28,000 works of art! Apparently no freedom of the arts exists, just more minor ones that don't affect as many people, such as the press (who reads?)
Wilder then had a difficult time casting the lead parts, two murdering adulterers. He wanted Barbara Stanwyck all along, but eventually had to challenge her to get her to take the image-shattering role, "are you an actress or a mouse?" After several refusals by actors, including George Raft, who had a knack for turning down breakthrough parts like Sam Spade in The Maltese Falcon, he convinced Fred McMurray to break his screen image of light romantic comedies to attempt something serious. His first scene with Stanwick, when he meets her at her home in a towel, uses his comedic skills along with some terrific dialogue.
Wilder also convinced leading actor Edward G. Robinson to take a non-starring character role, meaty enough for at least two important speeches that Robinson absolutely nailed. Crime novelist Raymond Chandler (The Big Sleep, The Long Goodbye) was brought in for his realistic dialogue, plenty evident here especially the opening scenes between Stanwyck and McMurray, but he, an introvert, and Wilder, an extrovert, didn't get along at all and never worked together again. Ironically,they were nominated for an Oscar together for their screenplay. Wilder later used Chandler as his model for his Oscar-winning Best Picture The Lost Weekend.
Double Indemnity was nominated for these 7 Oscars (but won none):
BEST MOTION PICTURE - Paramount (Going My Way won!)
DIRECTING - Billy Wilder
ACTRESS - Barbara Stanwyck
CINEMATOGRAPHY (Black and White) - John Seitz
WRITING (Screenplay) - Billy Wilder, Raymond Chandler
MUSIC (Music Score of a Drama or Comedy) - Miklos Rozsa
SOUND RECORDING - Paramount Studio Sound Dept, Loren L. Ryder, Sound Director
Other classic film noir: Out of the Past, The Night of the Hunter, Panic in the Streets, D.O.A., The Postman Always Rings Twice, The Big Sleep, The Maltese Falcon, The Third Man.
Modern Noir: Wait Until Dark, Diva (France), Chinatown, Shoot the Piano Player (France), House of Games, Taxi Driver, Blood Simple, Body Heat, The Silence of the Lambs. The style is also clearly evident in parts of other classic films such as In the Heat of the Night, The Godfather, Batman, Who's Afraid of Virginia Woolf, The Hustler, and The Departed.
Thanks to Beth G for suggesting Double Indemnity