This adaptation of the Raymond Chandler novel 'Farewell, My Lovely', renamed for the American market to prevent filmgoers mistaking it for a musical (for which Powell was already famous) has private eye Philip Marlowe hired by Moose Malloy, a petty crook just out of prison after a seven year stretch, to look for his former girlfriend, Velma, who has not been seen for the last six years. The case is tougher than Marlowe expected as his initially promising enquiries lead to a complex web of deceit involving bribery, perjury and theft, and where no one's motivation is obvious, least of all Marlowe's.
A small, seemingly innocuous plastic reel of film leads surveillance specialist Tom Welles down an increasingly dark and frightening path. With the help of the streetwise Max, Welles relentlessly follows a bizarre trail of evidence to determine the fate of a complete stranger. As his work turns into obsession, he drifts farther and farther away from his wife, family and simple life as a small-town private eye.
Kansas City in the 1930s: private investigator Mike Murphy's partner is brutally murdered when he tries to blackmail a mobster with his secret accounting records. When a rival gang boss goes after the missing records, ex-policeman Murphy is forced to team up again with his ex-partner Lieutenant Speer, even though they can't stand each other, to fight both gangs before KC erupts in a mob war.