Charade (1963)

Regina is about to divorce her husband when she finds that he has been murdered after converting every penny they owned to cash, which is also missing. She meets Cary Grant who changes his name every 15 minutes or so and is interested in her husband's money, which seems to have come from a WWII payroll he stole. His partners in crime are also very interested in where the money is, as he stole it from them as well. Everyone assumes Regina MUST know where the money is. The situation becomes more tense when the searchers begin turning up dead.

Regina Lambert returns to Paris from a ski holiday in Switzerland to find that her husband has been murdered. She is later told by CIA agent Hamilton Bartholemew that Charles Lambert was one of five men who stole $250,000 in gold from the U.S. government during World War II, and the government wants it back. The money was not found among his possessions, and Regina can shed no light on its whereabouts. Later that day she is visited by Peter Joshua, whom she had met briefly while on holiday. When her husband's former partners in crime, who were double-crossed by Charles, start calling her looking for the money, Peter offers to help find it. Thus begins an elaborate charade in which nothing is what it seems to be.