Triumph of the Will
5
Possibly the best, and with the perfect hindsight of history, the most frightening propaganda film ever made. Riefenstahl's documentary covering a Nazi rally in Nuremberg in 1934, has a terrible beauty about it, from the opening sequence of Hitler's plane descending from the clouds, its shadow growing across the ancient city, to the geometric rigidity of the rally itself. Watching it after the terrible events that came in its wake is like watching a dance of death, but it is a sly and seductive dance indeed.
Here is the stunning opening sequence of the plance descending. As fine a bit of cinema, in as evil a cause as I think has ever been created.