Michael Sheen has revealed what is in store for his character when his hit show Masters Of Sex returns later this year.
The Welsh actor plays Dr William Masters in the Channel 4 drama about the pioneering research into the science of human sexuality, which was celebrated at television festival Paleyfest in Los Angeles.
The first series of the show ended with the uptight doctor in professional and emotional turmoil confessing his feelings to his research partner Virginia Johnson, played by Lizzy Caplan, and Michael said showing that duality in his character was a highlight.
Speaking on the red carpet, Michael said: "That was one of the things I loved about the storyline for him. He begins season one as the most defended, guarded, invulnerable man in the world and he ends the season standing there in the rain saying how much he needs someone, the most vulnerable man.
"I love that kind journey but as with most people who aren't comfortable with being vulnerable, I don't think that is going to last and in fact the more the pendulum swings one way the more it has to swing the other way, so there is something in him that has to punish everyone who makes him vulnerable."
The show is frank in its depictions of nudity and sexuality and Michael's co-star Lizzy said that initially made her nervous.
Dressed in a long white dress with bright red shoes, Lizzy said: "I was nervous before we started shooting when I was given a rough overview of what was to come, that was intimidating, but as soon as I step into her clothes and her mindset it all makes such sense to me.
"Maybe I would be more uncomfortable if our show was run by hyper sexualised men but it is run by women and I don't feel like one beat of it is gratuitous, even the nudity and the sex, and I stand behind it, if I didn't I don't think I would shoot the scene."
Masters Of Sex returns to Channel 4 later this year.