http://www.imdb.com/title/tt0493459/
IMdb rating: 7.6/10 
Documents a history of the MPAA ratings board. Talks to numerous directors and actors about the censorship of their movies before they could be released. Includes directors, Kevin Smith, Matt Stone, John Waters, Darren Aronosfsky, Maria Bello, Atom Egoyan. Director, Kirby Dick hires a lesbian family of private investigators to find out the names of the MPAA ratings board and see if the raters are actually parents of children 5-17 like the MPAA tells American parents they are.