Again Hogan uses Klink to deliver information to the Underground but Klink is arrested by the Gestapo for treason on other grounds. Thus Hogan and his men must find a way to free Klink before the Gestapo finds the info on him.
Hogan's assignment is to discover the secrets of a new bomb (the "Chicken Hawk") that seeks out radio signals, and think of a way to stop its manufacture.
Burkhalter's niece is getting married and by having LeBeau design her wedding gown, Hogan is going to contact an underground agent, and later free him after capture by the Gestapo.