The plot revolves around a series of couples in Monte Carlo, Monaco. Augie Morosco (John Candy) is a reformed gambler whose wife Elena Morosco (Ornella Muti) ,who plays a character similar to her role in Oscar, is in the process of making a business deal, Neil Schwary (James Belushi) is a gambler looking to hit it big and whose wife Marilyn Schwary (Cybill Shepherd) is hoping to buy designer clothes. Julian Peters (Richard Lewis) and Phoebe (Sean Young) have met in Rome and are trying to return a dachshund to the wealthy Mrs Van Dougan.
Mrs Van Dougan is found murdered and the interactions between Julian and Phoebe and the other couples begin to look increasingly suspicious, with Inspector Bonnard (Giancarlo Giannini) having to unravel the clues. Over the course of the film, Augie returns to gambling, Elena has an affair and Julian sells and buys back the dog.