Peter O'Toole stars as Murphy, a stranded Irish merchant seaman who is the sole survivor of a WWII German U-boat attack in foreign waters. Rescued by Louis (Phillipe Noiret), a French oil engineer, he is taken to a small village hospital and treated by Doctor Haiden (Sian Phillips), a strong-willed and beautiful British doctor. Despite the impending end of the war,m Murphy is haunted by visions of the bloody attack on his boat and fellow sailors and will not rest until he has revenge. The German navy is still in hiding nearby; as Murphy recuperates, he learns of a derelict seaplane that he rebuilds in order to mount his own private campaign against the Germans. Against the backdrop of the remote tropical village, Murphy teaches himself how to fly the run-down plane, and with a rock start and some daredevil flying he begins his plan of attack, making homemade explosives with Loui's help. Despite the threat of death and his ever-growing fascination with the beautiful doctor, Murphy is determined to win his own war and will not rest until he sees the German U-boat destroyed.