For as long as crime boss Albert Mendoza (Everett Sloane) has been running a notorious ring of hired hit men, District Attorney Martin Ferguson (Humphrey Bogart) has been hunting him down. But Ferguson cuts a deal with Mendoza's henchman Joe Rico (Ted De Corsia), and the mob boss is finally arrested. However, Rico dies mysteriously before he can testify against Mendoza.

A film projectionist longs to be a detective. He puts his meagre skills to work when he is framed by a rival for stealing his girlfriend’s father’s pocket watch.