Movie ratings — those Rs, PG-13s and NC-17s — won't look nearly as innocuous after seeing this sharply observed and funny investigation of the Motion Picture Association of America. The MPAA keeps the rating process completely secret, but filmmaker Kirby Dick and the private eye he hires discover a hidden society, closed to filmmakers but overseen by religious figures. As Dick goes deeper, we start to understand how the MPAA's ratings system reflects some of American society's troubling propensities, including the glorification of violence, a fear of sex of any kind and a paranoiac attitude towards gays, lesbians and other nonconformists. Using animation, interviews and, most of all, his substantial powers as a storyteller, Dick turns This Film into a potent mix of black comedy, social critique and old-fashioned muckraking. (JS)