The time is 1943 and the hero an English submarine named Setter that has been commissioned to make a dangerous journey to occupied Norway. There a Bishop who has been uncooperative toward the Germans waits for his family to be taken to England. We follow the Setter as it makes its trip and safe return and get to know something of its structure and its crew. Though adults may find the action at an elementary level and the death of one character poignant if not tragic, young readers graduating from teenage seafaring tales will probably find this quite exciting.