The Nice Adventure.

Hoping to scare wealthy young Bernard into getting married to his longtime fiancee Georgette, a phony fortune-teller is hired to inform Bernard that he is to die very soon. But thanks to a case of mistaken identity, the fortune-teller delivers this message to middle-aged gym instructor Étienne. Instead of heading towards the altar, however, Étienne decides to live his last few months on earth to the fullest -- and as a result becomes a millionaire at the gaming tables of Monte Carlo. Upon learning that he isn't going to kick the bucket after all, our hero pretends to be at death's door anyway, all for the purpose of patching up the rocky romance between Bernard and Georgette.