Master of Sex

By now, Masters of Sex star Michael Sheen has gotten used to nudity and watching sex acts performed in front of him.

"We've seen so many people do bizarre things in front of you, you get used to it," Sheen said at the Television Critics Association fall previews on Tuesday. "There's a naked woman in front of you masturbating ... and you almost don't notice. I actually broke that barrier on the show."

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On Showtime's new period drama Masters of Sex, Sheen plays William Masters, who teamed up with partner Virgina Johnson (Lizzy Caplan) to pioneer research of the human sexual response beginning in the late 1950s. As researchers, Masters and Johnson observed many sex acts -- solo and with couples -- but also participated in the studies. Oddly enough, the conventional love scenes posed no problems for the cast, but the ones shot in the laboratory settings, where the characters are hooked up to machines to measure their physiological reactions, were a challenge.

"A couple making love — that is far easier than some fluorescent lighting, wired up, don't kiss, don't look at each other, penis in vagina [scene]," said Caplan. "Not being able to kiss, you feel even more naked, so to speak." Sheen, whose resume is filled with unconventional sex scenes, agreed. "It's a scientific thing where you're not supposed to have any emotional response. That's really difficult."

Masters and Johnson used prostitutes first and then enlisted volunteers for their research, which meant a revolving door of actors joining the onscreen sexcapades for limited periods of time. Making the set as comfortable for these guests was of paramount importance. "We want people to keep coming on this show and take those risks," he said. "We aren't all tee-hee-hee-ing about it. We're all straightforward."

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Teddy Sears, who plays the randy Dr. Langham, particularly appreciated this tone on set since this was his first-ever sex scene. "Director John Madden told me, 'I want to protect your modesty.' He was like a nice grandfather, and then would say, 'Grab her bum' and 'put your hand on her nipple.' The environment is very caring."

And although knowledge about the human sexual response has come a long way, it's still not a part of open, everyday conversation. "People are surprised by the frank discussions of sex on the show more than the portrayal of sex," executive producer Sarah Timberman said. "The things these people talk about are not generally talked about. It makes for interesting talk in the writers' room."

The light Masters and Johnson's research shone on female sexuality especially created more equality in the bedroom. "I was fortunately raised in a household where questions were encouraged and not judged ... I was not dirty for asking these questions," Caplan said. "Virginia Johnson did this for millions of women, for generations of women to not feel ashamed. Before Masters and Johnson, women were told [sexual problems were] all their fault ... and that's some bullsh--."

Masters of Sex
premieres Sunday, Sept. 29 at 10/9c, right after the third season premiere of Homeland.

(Full disclosure: TVGuide.com is owned by CBS, the parent company of Showtime.)