In 1944, during the last stages of the war in Europe, American officers Paul MacDougall (Heston) and Joseph Contini (Guardino) are sent to Italy to act as spies for the Allies, even though they have no experience in espionage. Working with Partisan resistance soldier Ciccio Massimo (Baccaloni), MacDougall and Contini send regular reports to their superiors by carrier pigeon. Contini also finds himself falling in love with Massimo's pregnant daughter Rosalba (Pallotta), while her sister Antonella (Martinelli) has her eye on MacDougall. Contini proposes to Rosalba, and Ciccio prepares a feast to celebrate his daughter's upcoming wedding. However, Ciccio prepares squab for the occasion, killing all but one of the carrier pigeons. Ciccio scrambles to replace them, but the new pigeons he finds are German, and they deliver MacDougall and Contini's messages directly into enemy hands.