In the bohemian Montmartre district of late-1950s Paris, Robert "Bob" Montagné--a habitual gambler and former bank robber who's been going straight for twenty years--finds himself flat broke after a long string of bad luck. In need of cash, the ex-gangster organises one last heist, setting his sights on robbing the safe of the casino at Deauville, allegedly crammed with as much as 800 million francs. Now, the stage seems set for a daring, winner-take-all final robbery; however, greed, blackmail, and death get in the way. Can Bob the Gambler get away scot-free?