From The Situationist:
The Celluloid Closet [from Wikipedia] is a 1995 documentary film directed and written by Rob Epstein and Jeffrey Friedman. The film is based on the 1981 (revised 1987) book of the same name written by Vito Russo. Russo researched the history of how motion pictures, especially Hollywood films, had portrayed gay, lesbian, bisexual and transgender characters.
The documentary interviews various men and women connected to the Hollywood industry to comment on various film clips and their own personal experiences with the treatment of LGBT characters in film. From the sissy characters, to the censorship of the Hollywood Production Code, the coded gay characters and cruel stereotypes to the progress made in the early 1990s.
The movie is posted, in five parts, here