Los Angeles police detective Joe Friday hunts down the killer of a mobster, Miller Starkie, focusing on West Coast mafia second-in-command Max Troy (played by Harris). The vendetta between Friday and Troy becomes increasingly bitter and personal as the film proceeds, leading to a brawl at a private card game between Friday, Frank Smith, and several of Troy's henchmen. A policewoman (Robinson) infiltrates Troy's nightclub and is able to obtain vital information on the Starkie killing.