Michael Sheen (The Special Relationship; The Queen) has replaced Paul Bettany in the lead role of Showtime's adaptation of Thomas Maier's book Masters of Sex: The Life and Times of William Masters and Virginia Johnson, the Couple Who Taught America How to Love, the Hollywood Reporter wrote. Lizzy Caplan (New Girl) co-stars as Johnson in the pilot, which is being directed by John Madden (Shakespeare in Love) and starts production next month in New York.