Wolf Brandin is in his mid-twenties and lives with his wife and child in East Berlin at the end of the 1950s. In West Berlin, the student of electrical engineering is recruited by the American secret service CIA. But Brandin immediately notifies the State Security of the German Democratic Republic and from then on lives a dangerous life as a double agent. When Brandin reaches the breaking point, his marriage starts to unravel because Brandin is not allowed to tell his family about his double life.