From Behind Closed Doors

Showtime’s “In the 20th Century” is a millennium-related strand of feature-length documentaries in which famous directors take on major subjects of their choosing. In the second of the six films, “From Behind Closed Doors,” filmmaker Robert Townsend delves into America’s fraught relationship with sex and sexuality, using New York’s Times Square as the focal point as he traces 100 years of sexual mores and practices.