"Super Size Me" (2004)
Morgan Spurlock used his outgoing personality and a hot-button topic to create a film that has defined his career. Examining the US's issue with obesity, Spurlock turned his camera to McDonald's and in the process changed the way we look at fast food. (In the movie he eats only from the McDonald's menu for one month.) This movie is a big part of why you see more healthy choices and no more "super size" option at McDonald's.