Piper "intrigued" by swinging fetish

'Doctor Who' / BBC1

Billie Piper has revealed that she is intrigued by the phenomenon of swingers' parties.

Piper, who stars as a prostitute in the new ITV2 drama Secret Diary of a Call Girl, has claimed that the fetish has always fascinated her.

She told the Daily Mirror: "I've always been intrigued by swinging parties."

The former Doctor Who star added that her now role as a hooker has allowed her to reveal a more sexual side to her personality.

The TV actress commented: "The sex scenes are choreographed. You talk about where your hand goes and where to put your body - it's a bit like dancing.

"This was a chance to be shockingly sexy. I've learned one or two things to take home..."

Piper announced last month that she has been talking to real life vice-girls to help get into character for the role.