Showtime's steamy hit Masters of Sex returns with new episodes on July 13, and the first peek has arrived! Michael Sheen and Lizzy Caplan are back as William Masters and Virginia Johnson, pioneers in sex research, and things have gotten even more dramatic since last season. William and Virginia are stuck navigating their personal and professional lives, and stuff hits the fan when Vivian (Rose McIver) confronts Virginia about her relationship with William: "You may get away with this now, but eventually people will catch on, and then all you'll be is old and ugly and alone." That relationship, by the way, looks like it might be less about research and more about a full-blown affair. Take a look!