In order to complete the task assigned by the Marshal, Capra felt that he had to learn something about documentaries immediately. He first asked the War Department to let him watch Rifenstahl's Victory of the will, which made him shudder. The more he thought about his reaction to the film, the more he felt that studying the film was the key to solving the problems he faced. If American soldiers watch the film, they will better understand why they are fighting. When Capra found that the United States still had hundreds of war newsreels and documentaries made by Germany, Italy and Japan, he managed to mobilize these films into his own hands. Later, he also felt the need to obtain relevant film materials from the allies of the United States, so he negotiated with the embassies of the Soviet Union and other countries. In the process, he also took a detour. One day, he was unexpectedly summoned to the Security Bureau of the War Department and sat opposite a bespectacled colonel. An expressionless male stenographer brought a questionnaire. The colonel announced that Capra would be arrested for violating military discipline and would be investigated. The colonel took out a picture. Capra knew at a glance that it was a picture of himself standing in front of the Soviet embassy: ".