Martin Harvey is a middle-aged office worker who lives in Chicago with his wife, Katherine, 16-year-old daughter, Caroline, and 11-year-old son, Ben. When he learns his recently deceased uncle has bequeathed him a 60' yacht once owned by Clark Gable, he decides to take his family to the island of St. Pomme de Terre ("Saint Potato") to retrieve it so he can sell it. Katherine resists the idea, but agrees after Caroline announces she has just become engaged.