Air Commodore Raymond has a thrilling new case for Biggles, Ginger, Algy and Bertie, now the Scotland Yard Air Squad.Instead of surrendering at the end of the war, commander Von Schonbeck of submarine U-517 escaped to the south Indian ocean. From his base on an uncharted island, he has been waging his own personal war, very profitably. Among other booty, he is known to have acquired a sizeable quantity of gold.