Claude Lanzmann directed this 9 1/2 hour documentary of the Holocaust without using a single frame of archive footage. He interviews survivors, witnesses, and ex-Nazis (whom he had to film secretly since though only agreed to be interviewed by audio).
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The Polish townspeople highlighted a big part of how Nazis were easily able to come to power. They weren't prejudiced to the point of wanting to kill them, but they were competitors. If the Jews went away, there were less businesses to compete against, less rivals in love. It was a horrendous system that allowed few to thrive, even prosper, and all they had to do was not look into the forest.