When Johnny Morrison returns home at the end of the war, he expects to receive a warm welcome from his wife. However, he makes the unpleasant discovery that she's been unfaithful to him with Eddie Harwood, the owner of the Blue Dahlia nightclub. After a heated and violent argument, he storms out of their house. Later that night, she's murdered--and Johnny winds up the prime suspect. Now, to prove his innocence, Johnny must find the real culprit. Among the suspects are the ruthless nightclub owner and a vicious gangster. Joyce Harwood, the estranged wife of the club's proprietor, lends Johnny a hand and the two fall in love while tracking down the killer. Two ex-service buddies also come to Johnny's aid: the shell-shocked Buzz Wanchek and George Copeland. Will Johnny solve the mystery before the police find him and charge him with murder?

This film noir classic was Raymond Chandler's first original story written directly for the screen.