Shipwrecked near a tiny island in a vast ocean, the Fisher family are guided to safety by a small pod of dolphins. Fleur, Alfie, Mia and their parents must learn to build shelter, find fresh water and hunt for food. Each of the children forms a special bond with one of the family of dolphins. Fleur adores the fun-loving, tail-walking Jazz. Mia names her dark-grey dolphin friend Stormy. And Alfie is saved from the shipwreck by Pearl, who always looks out for him. Alfie and Mia don't realize how much they rely on their older sister until she is taken ill with a mysterious sickness. They'll do anything to save her - and perhaps the dolphins, too, can help Fleur pull through.