The Killing (1956) on Netflix

Ex-convict Johnny Clay tells his girl friend, Fay, he has plans for making money, and indeed he has. He rounds up a gang and brings them in on a seemingly fool-proof scheme to rob a race track of $200,000. The first thread unravels when Sherry Peatty, wife of gang-member George Peatty, tells her boyfriend Val Cannon about the plan, and he cuts himself in on that action also. The robbery is completed and the gang goes to the hideout where Johnny will join them later. Val sticks up the robbers, a shot is fired, and all hands are soon dispatched. Johnny, with the money in a suitcase, joins Fay at the airport. And the fat lady still hasn't sung.