Ted Jackson (Elvis Presley) is a U. S. Navy diver who discovers a sunken ship during a his final dive while disarming an underwater mine. He goes to find the granddaughter of the ship's owner, Jo Symongton (Dodie Marshall), to check the manifest for the vessel and is convinced that there is some sort of treasure on board. He contacts Judd Whitman (Pat Harrington), a former business partner, to provide seed money for the salvage operation, and local shop keeper Captain Jack (Frank McHugh) to provide additional equipment in trade for shares of the treasure.