On March 24, 1944, in the Ardeatine Caves outside Rome, one of the most infamous atrocities of World War II occurred -- the mass execution of 330 Italians in retaliation for the deaths of 33 Germans. The book Death in Rome contends that Pope Pius XII knew of the German plan but did nothing to stop it. In this film adaptation, Richard Burton plays Col. Herbert Kappler, a Nazi officer torn between his devotion to Hitler's cause and his love for Italy when he is ordered by his superior officer, Gen. Kurt Maelzer (Leo McKern), to see that this execution is carried out. Opposing the Germans and reacting against the silence of the Pope is Vatican priest Don Antonelli (Marcello Mastroianni), who chooses to die with the Italians rather than continue to act as a middleman between the German army and the Romans.