Showtime has found its sex masters: Michael Sheen and Lizzy Caplan will star in the drama about groundbreaking sex and sexuality researchers, the network announced today. Interesting! Masters of Sex is based on Thomas Maier's biography Masters of Sex: The Life and Times of William Masters and Virginia Johnson, The Couple Who Taught America How to Love, which traces Masters and Johnson's relationship through its unusual incarnations: She started as his assistant in 1956 — a position that included having sex with Masters as part of their research. The two married in 1971, divorced in 1993, and along the way published the most comprehensive sex research of their era and prompted Playboy to print the word "clitoris" for the first time. This show is going to be like Kinsey, but with better clothes.