SHOWTIME released the key art and first footage from season four of its critically-acclaimed drama series MASTERS OF SEX. Premiering on Sunday, September 11th at 10 p.m. ET/PT, MASTERS OF SEX stars Emmy and Golden Globe nominee Michael Sheen and Emmy nominee Lizzy Caplan as real-life pioneers of human sexuality, William Masters and Virginia Johnson. Season four begins in 1968 and will take viewers into the “swinging ‘70s,” during which time the series’ characters will take on new partners both professionally, personally and sexually.