While the general public is familiar with the MPAA ratings that accompany the movies they watch–G, PG, PG-13, R–and what the ratings mean, it is safe to say that most moviegoers don’t really know, or care, what the Motion Picture Association of America is or how its members decide what film gets what rating. But documentary filmmaker Kirby Dick thinks that consumers should be aware of the intricate politics and enormous hypocrisy of the MPAA. With satirical humor–not to mention two female detectives who hunt MPAA board members down and make them confess everything–he unravels the mystery of the MPAA’s secretive ways in “This Film Is Not Rated,” which opens in limited release this weekend before airing on the Independent Film Channel this fall.

In theory, the MPAA is simply a voluntary ratings system in which movie executives from different studios serve for a predetermined length of time on the ratings board that hands out a rating based on a film’s content. No filmmaker is required to submit his or her film to the MPAA ratings board for approval. However, the MPAA works closely with the National Association of Theater Owners, and they like the ratings system. So if a film is not rated, or has the dreaded NC-17 rating, the chance of a film having commercial success is slim.

However, the MPAA system becomes even more complicated in light of the fact that the members of the board are from conflicting studios, so there’s just a teeny bit of sabotage going on in the ratings decision making process. For example, if you think a fellow studio has a potential blockbuster on its hands, maybe you want it to get an “R” rating instead of a “PG-13″ rating, so its audience will be smaller. On the other hand, all studio execs want to reach that target demographic of young white males, so violence and women’s breasts don’t receive the same kind of rating as male nudity or other controversial elements.

Dick supports these claims by interviewing numerous directors, including Kevin Smith (“Clerks”) and Matt Stone ( “South Park”), who have attempted to do battle with the MPAA and have often lost those battles. With both humor and anger the directors recount the notes they have been given by the MPAA instructing them on how to achieve a different rating by editing the film differently–even though the MPAA is not supposed to give such suggestions.

I don’t agree with some of the conclusions “This Film Is Not Yet Rated” comes to when exploring how to solve the problem of the MPAA , but I still think this movie is important viewing for anyone who has bought a movie ticket based on a movie’s MPAA rating. The MPAA does not exist to be a friendly moral gatekeeper to guide or protect you or your family but is a corrupted system that is arbitrarily legislating morality and censoring content. And it’s the degree of corruption that makes “This Film” so shocking.

Oh, and just in case you are wondering, “This Film Is Not Yet Rated” received an NC-17 rating for its objectionable content.