Welsh thespian Michael Sheen has a knack for playing real people. No really. He’s portrayed everyone from TV broadcaster David Frost (Frost/Nixon) to prime minister Tony Blair (The Queen) to English football manager Brian Clough (The Damn United). And lately, he’s been dazzling on the small screen as William Masters in Showtime’s Masters of Sex. The man himself was an actual Midwest gynecologist who specialized in fertility problems before teaming up with Virginia Johnson—played by Lizzy Caplan in the series—to write the groundbreaking 1966 book, Human Sexual Response, which included an analysis of 10,000 orgasms and more.

Sheen admits he plays Masters as a monster, a product of his physically abusive childhood, but his character’s bravado barely hides a slew of insecurities. And Masters’ mix of contradictions, brilliance and weakness, just intrigues Sheen as an actor. Of course, he’s also the guy that ladyfriend Sarah Silverman called “my love, Mr. Fancypants Sheen” during her Emmy acceptance speech last year.

Taking a break from filming Season 3, which premieres this Sunday at 10/9c, Sheen gave us the skinny on sex, love and why we still haven’t figured it all out just yet.

“That’s what was exciting about the project, to do something through the lens of history that’s actually about what we’re going through now. We’ve learned all kinds of things about sex, sexuality and relationships, but we’re still dealing with the same problems all the time.”

Season 3 kicks off in 1966, which is a pretty rich time period to mine, right?
That period 1966 to ’68 was huge with so many different things going on: Vietnam, the Civil Rights struggle, the growth of feminism, political movements, the sexual revolution. It was such a huge upheaval moment. Although, you have to remember, we’re in St. Louis. The sexual revolution happened mostly in New York and California. I was listening to something about 1967 and the Summer of Love, and they were saying, ‘Yeah, but it was only the summer of love in San Francisco!’ It wasn’t the Summer of Love anywhere else, mostly. The army was on the streets and campuses. So when you talk about the sexual revolution, there’s lots of different versions of that going on. It was a slower change for the majority of Americans.

Human Sexual Response is just released in this new season. How does the resulting notoriety impact your characters?
The book is in the public realm now and we’re public figures. For Bill, you’d think he’d find that very difficult, and Virginia is much more relaxed and better with people, but it all goes slightly different—she’s pregnant and that has ramifications. As always with these characters, nothing ever goes in a simple straightforward manner. But once you become a public figure it’s not just about the work, and just the medical establishment, it’s the world and how it responds to him, and that absolutely terrifies him.

The real book came out almost 50 years ago, but the issues are still relevant today, no?
Yes, it feels very resonant to our values today, certainly to my values. I’m not really interested in doing a kind of museum piece; that’s what was exciting about this project, to do something through the lens of history that’s actually about what we’re going through now. We’ve learned all kinds of things about sex, sexuality and relationships, but we’re still dealing with the same problems all the time. There’s more information but sometimes the more information, the harder the challenge.

Despite all we now know about sexuality, what are the underlying issues that still affect human relationships?
Ultimately you come back to the same question: How do you navigate being vulnerable with somebody? Because the more vulnerable you become with someone, the higher the stakes are in terms of what you need and want from them. And then the more frightened you are at the risk of losing them. And yet in order to be human, you have to be vulnerable, and Bill has more trouble being vulnerable than any other character I’ve played. That continues to fascinate me. Overall, it’s not just to do with the ’50s or ’60s; it’s a universal and timeless challenge, about vulnerability and intimacy, just being a human being.

Like many men, Bill has some skeletons in his closet. How does that impact him moving forward?
He’s a man who likes to compartmentalize, and this is very prevalent for people who’ve suffered some form of abuse as children. Part of what that’s telling a child is that the universe is chaotic, totally devoid of order and meaning because the one person who should be looking after you the most is actually abusing you, so anything is possible at any time, and you can’t trust anything. That lends itself to someone constantly looking to exert control in any area you can. And it leads you to compartmentalize things, keep them in boxes, keep them separate, and then also try to manipulate things in your own life. So the idea of his own sexuality, which requires a certain loss of control, is very frightening to him.

But can this delusional sense of “order” maintain itself?
At the beginning of the story, we see a man presenting an image that isn’t authentic. Then we start to see that sort of unraveling because a woman (Virginia) comes along who speaks to that buried, yet authentic and uncivilized part of him. And this threatens to decimate everything he’s created in a controlling way. Yet, he’s ultimately on a trajectory of change; he’s not going to like it and will kick and scream getting there, but he wants to go there. I’ve never seen that in a character I’ve played.

Women since Virginia have been trying to balance work and motherhood. How do you think they’re doing?
Specifically for women, that juggling act has been very difficult, although it’s evolved over time. Virginia’s journey expresses that. I’ve heard so many women today talk about the idea that if you’re a working mother, the hardest challenge is that you never quite feel that you’re matching up in either area. You constantly feel like you’re just failing. With Virginia, there’s definitely something about the idea of a woman who actually wants to devote more time to work, yet feels guilty about that. And how you can be punished for that by society. Going into the new season, she’s struggling with what that means, the idea of maybe choosing work over children. And how kind of awful that is in her mind and in the mind of society.

There’s an old saying: ‘Never work with children or animals.’ How does having a baby on set play out?
[Laughs] It’s a nightmare working with babies and very young children, and very challenging. Hopefully, you can keep it to a minimum. Then again, if you use it judiciously, then it can be really effective. [Laughs] But I don’t like working with babies that often!

How do you juggle your own career and parenthood?
The mother (Kate Beckinsale) of my daughter and I are not together anymore and that creates all kinds of challenges. In some ways, work has made things easier because it gives you something else to focus on when you’re not with them. But, it also makes it more complicated because in my line of work, I’m not always working in the same city. Doing this show has helped that a lot because for the first time I’ve been able to work for a long period of time in the city (Los Angeles) where my daughter is, and that was a big factor in getting involved with it.

To paraphrase Tina Turner, what’s love got to do with it all?
I don’t really know what love means—is it about opening up and showing a side of yourself you’ve kept defended all your life? That’s what we’re trying to explore in the show in a way, how much is it about the other person, how much is it about you, how much about you changing and finding aspects of yourself that were hidden to you, and then someone comes along and opens that up in you. Does that describe you or does it describe them? Or does it describe the relationship? And what if then, that person leaves you? What does that say about you? And somewhere in all that complication is what we call love. It seems like a sort of bow that we tie on something, and I’m not entirely sure what it means.

And love sure changes from when we were younger, right?
When we’re younger, what we call love is sort of just a combination of things. The first period of any relationship is more about you rather than the other person. The problem is when it starts to become about the other person. ‘Oh, no, no, I don’t know if I like that!’ You’re ultimately just bathing in what the other person feels about you, but is that love? I don’t know. Love is probably about how you cope with it when it gets tough, and that makes a better relationship. Then it’s about two people and the moments that you find within that, that make you suddenly go, Ooh, this is amazing! Then it’s kind of earned.