"Master of Sex" cast Lizzy Caplan, Caitlin Fitzgerald and Annaleigh Ashford opens up on their show's funny moments and filming the second season of the critically-acclaimed TV series. For the female stars of show, filming it is constraining thanks to the prohibitive nature of the undergarments they wear.

Portraying their 1950's-era characters, the girls of "Master of Sex" revealed how they shared secrets on the easiest way to manage their dreaded girdles. Caplan who plays Virginia Johnson brought up the topic about the undergarments and revealed that she insisted to wear the "period appropriate undergarments" to get into the character.

"Undergarments can change everything about how you walk, how you talk, how you move," says Annaleigh Ashford who plays prostitute Betty DiMello on the Showtime show. "So thank God we wear full-out undergarments from the era. But also it was very hard to pee back then. You have to ask somebody to help you when it's time to go pee. I mean - I haven't done that since I was like 4."

Micheal Sheen who plays Dr. William H. Masters on the series also agreed and joked: "So do I. I actually insist on wearing Lizzy's."

Held last Monday, March 24, the PaleyFest panel get intimate with the cast at Hollywood's Dolby Theater as the cast shares titillating topics about love and on-camera copulation. Based on the 2009 Thomas Maier biography where the show is based, "Master of Sex" series executive producer Michelle Ashford revealed that casting for the show was not easy.

"We were looking for ferocious intelligence and people who had an unconventional bent to their work and to the roles that they had chosen," says Ashford on casting Sheen as the famous OB/GYN doctor and Caplan as Dr. Masters lab partner.

"I really did not anticipate the reaction to be so in line with what we were going for," say Caplan after the show's first season review. That's never happened to me before in my career. When we first aired, we were seen as a show that didn't degrade women in the least. It was a feminist story that we were trying to tell. It was so refreshing and really proves how smart the audience is and that it deserves more."

"Master of Sex" season 2 is scheduled to premiere on July 13 with new stars including Allison Janney, Beau Bridges, Brant, Keke Palmer and Danny Huston.