In Paris, Bob Montagne is practically synonymous with gambling -- and winning. He is kind, classy and well-liked by virtually everyone in town, including police inspector Ledru. However, when Bob's luck turns sour, he begins to lose friends and makes the most desperate gamble of his life: to rob the Deauville casino during Grand Prix weekend, when the vaults are full. Unfortunately, Bob soon learns that the game is rigged and the cops are on to him.