‘Masters of Sex’ Showrunner Previews New Faces and Challenges for Masters and Johnson in Season 4

Not unlike its real-life subjects — pioneering sex researchers William Masters and Virginia Johnson (played by Michael Sheen and Lizzy Caplan) — the Showtime drama Masters of Sex, has been through some turbulent times. Season 3 proved a particularly divisive year, with heavily fictionalized storylines involving the duo’s children, as well as the infamous “gorilla episode,” turning off some viewers who once championed the provocative series. Speaking with Yahoo TV in advance of Masters’ fourth season premiere, which debuts on Sept. 11, showrunner Michelle Ashford sounds well aware of the mixed reaction some of last year’s creative choices inspired. “Lizzy’s days of cavorting with gorillas are over, I think we can safely say that,” she jokes.

But Ashford also isn’t dwelling on the past, and hopes that viewers will similarly look forward to a new year that will bring new challenges and new faces into Masters and Johnson’s orbit, as the pair continue to navigate their complicated personal and professional lives. “What makes their story interesting is that they were never in the same spot at one time, but there were these periods where everything came together for them. They hung in there together for so many years. It’s the most bizarre love story I’ve ever seen.” Here are five things that Ashford shared with us about the upcoming season.

The Swinging ’60s Will Give Way to the Seedy ’70s

Because Masters and Johnson’s careers spanned some four decades of 20th century history, Masters of Sex has been known to take big leaps forward in time, at one point skipping ahead three years in the space of a single episode. Season 4 will cover a roughly three-year timespan as well, from 1968 to 1971, but Ashford promises it will be a more “graceful and gradual” transition. “I think we’ve found that unless there’s a point to the time jump, it’s better to just gradually move the timeline along.” Looking forward to next season, and potentially beyond, the writing staff is in the process of discussing how far forward in time the series will venture before shutting off the lights for good. (As of now, Showtime has yet to announce a Season 5 renewal.) “Masters and Johnson did work into the ’80s, and that would provide a real full circle look at the sexual revolution,” Ashford says. “They started in the ’50s when everything was hidden, and then when you get to the ’80s there was this real reverting to ‘What have we wrought?’ So we’re talking about it right now, what to do with the last part of this story.”

Masters & Johnson: The New (Old) Brangelina?

Last season saw the publication of Bill and Virginia’s revolutionary 1966 tome, Human Sexual Response, and the attendant publicity thrust them into the harsh glare of the public spotlight. By 1968, they’re established national celebrities, which is a big change for two researchers from sleepy St. Louis. “They’re beginning to understand that there’s a whole entity called ‘Masters & Johnson’ that doesn’t have much to do with them anymore personally,” Ashford says. “It’s like the Brangelina thing. At some point, a duo becomes so famous that it has its own life.”

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Masters After Dark

Now that they’re officially part of the “In Crowd,” Masters and Johnson frequently enjoy hobnobbing with other A-list celebrities, including Playboy founder Hugh Hefner (John Gleeson Connolly). “In real life, Masters and Johnson and Hefner had a long working relationship and were friends. They were like-minded in their thinking about the sexual revolution.” Connolly made his first appearance as Hefner in Season 3 but will enjoy a larger role this year. “It’s uncanny how much he looks and sounds like him.” As for what the real Hefner thinks of his stand-in, Ashford isn’t sure. “We haven’t reached out to him. Hugh had his own show [2011’s short-lived The Playboy Club], and we decided to keep it separate.”

Scrubbing In

With Bill and Virginia frequently off burnishing the “Masters & Johnson” brand — and being reluctant to work with each other, due to her whole “eloping with Josh Charles” thing — they’ve hired two new doctors to join their thriving practice. The Big Short’s Jeremy Strong will play incoming psychologist Art, while Nurse Jackie’s Betty Gilpin portrays Nancy. About a Boy’s David Walton also has a prominent recurring role as their attorney, Abe Perlman, while Getting On’s Niecy Nash will regularly appear as an AA chapter leader who becomes a patient. But the guest star who perhaps thrills Ashford the most is Tony-winner Kelli O’Hara, who will play an old flame of Bill’s that re-enters his life. “I’m just going to ask her to sing to me all day.”

Goodbye Gloomy Gus

Since the series began, Bill Masters has been a textbook example of a “cold fish,” and his passive-aggressive attitude has frequently upset the characters on the show and viewers at home. Ashford credits Sheen with not pulling punches on Masters’s unpleasant demeanor, which is well documented in the real world as well. At the same time, she wants to let viewers know that it was all for a purpose. “People were really struggling with Masters, they were saying he was unrelenting in his being difficult. It was always by design that he would undergo a real transformation, and you see it this season. And by the way, it’s true in real life. So if you were tired of Bill Masters being grim, tune in!”

Masters of Sex premieres Sept. 11 at 10 p.m. on Showtime.