Nazi Germany's prized airship is threatened with sabotage, so Col. Franz Ritter (George C. Scott) is charged with its safety. As the massive zeppelin lifts off for a journey to the United States, Ritter investigates the passengers, looking for a potential bomber. Could it be anti-Nazi Countess Ursula von Reugen (Anne Bancroft), suspicious gambler Emilio Pajetta (Burgess Meredith), shifty advertising man Edward Douglas (Gig Young) or even the pilot, Capt. Pruss (Charles Durning) ?