After boxer Swede (Burt Lancaster) is gunned down by a pair of contract killers, insurance investigator Jim Reardon (Edmond O'Brien) sets about piecing together the motives behind the murder. Swede's story is revealed in flashback - how he became involved in the crime world of Big Jim Colfax (Albert Dekker), only to be seduced into armed robbery by Colfax's glamorous moll, Kitty Collins (Ava Gardner).