Rated X: A Journey Through Porn 1999 on netflix

Director Dag Yngvesson begins making a documentary about the porn industry, until he is asked by a desperate director to shoot film for his next adult movie. After agreeing, he is led deeper and deeper into the world of porn, speaking frankly with many of the industries most famous icons (Jeanna Fine, Bill Margold) and a 19-year-old newcomer named Selena who discusses her career choice on film with her mother. Viewers are invited into many areas of the industry previously not discussed including the private lives of its stars and the inner workings of the industry, in particular how directors go about casting their stars.