Michael Sheen and Lizzy Caplan are Showtime's New Sex Symbols

Michael Sheen and Lizzy Caplan are the new Masters of Sex.

Showtime has tapped the pair to headline its drama pilot based on 1960’s human sexuality pioneers William Masters and Virginia Johnson.

The project is based on Masters of Sex: The Life and Times of William Masters and Virginia Johnson, The Couple Who Taught America How to Love, Thomas Maier’s book about the 1960s human sexuality pioneers.

Sheen, of Frost/Nixon and 30 Rock fame, assumes the role of William from Paul Bettany, who dropped out last month for undisclosed reasons.

Indie staple Caplan is currently in the midst of a multi-episode arc on New Girl.