Anthony Andrews plays a young Lt. in the early days of World War II who is assigned to a UXB unit. UXB is the signal that an aerial bomb has not exploded. Andrews' job is to deactivate bombs made by German technicians some of which have fuses specifically designed to kill him. The series takes us through his maturation as an officer, a love story with Judy Geeson, and the stresses and strains of wartime on the civilians and military in England.