Morgan and Catherine Norvell have their future plans ready. In Monte Carlo, their sailboat is stocked. From there they are going to sail to Malta and live on the boat for a year. They have bought some real estate with an old ruin of a hotel on it, which they are going to rebuild. A few days before they are about to start, they meet Gil and Ronnie Freeland. They would give anything to join them for a couple of days on the sea, and no sooner said than done, all four of them are enjoying the sweet life on the boat. The Norvells soon discover that it was a big mistake to invite them on board...