The retelling of June 6, 1944, from the perspectives of the Germans, US, British, Canadians, and the Free French. Marshall Erwin Rommel, touring the defenses being established as part of the Reich's Atlantic Wall, notes to his officers that when the Allied invasion comes they must be stopped on the beach. "For the Allies as well as the Germans, it will be the longest day"
When mild-mannered Martin Harvey finds out that he has inherited a vintage yacht, he decides to take his family on a Caribbean vacation to retrieve the vessel. Upon arriving on a small island and realizing that the ship is in rough shape, Martin and his family end up with more than they bargained for as the roguish Captain Ron signs on to sail the boat to Miami. It doesn't take long before Ron's anything-goes antics get the Harveys into plenty of trouble.