Hearing about some of the graphic scenes, it’s not surprising her husband isn’t a fan.
“I had one scene where I had to pretend to be an array of farmyard animals while having sex,” says Billie. “That was quite humiliating. I wasn’t annoyed with anyone for asking me because when I read it on paper I was laughing and completely game to do it.
“But on the day I thought, ‘oh wow’ because it’s not the best thing to do and you don’t exactly feel amazing doing it. But you just have to crack on. It wasn’t until afterwards that I felt like having a meltdown. I wasn’t upset, just embarrassed, and I really felt I needed to have a word with myself.”
Would she be happy for Laurence to be filmed acting in similar sex scenes? “No way!” she laughs.
“It would not be OK. Fine, I have extreme double standards, but I couldn’t handle it. I’d be down on set hawk-eyeing everyone, being an overwhelming pain.
“Well, to be fair to me he has had kissing scenes in the past, which I’ve handled with good grace – although he might say otherwise.”
With two iconic roles behind her – Secret Diary’s Belle du Jour and Doctor Who’s Rose Tyler – what’s next for Billie Piper?
“Well it’s an absolute no for music,” she says. “That’s very much in the past for me. And it’s totally the end of Doctor Who for me, too. I can’t imagine anything would bring me back, and they’re done with Rose.
“They’ve got this great new set up with Matt Smith and Karen Gillan and it works brilliantly. So there’s no way in the world it will happen again for me – well not for the foreseeable future.
“Both Belle and Rose have been brilliant for my career, but I don’t know yet if they might become curses some day. They haven’t been so far, but who knows? The problem with something like Secret Diary is that you could end up getting endless sexy scripts and a long line of sexual predator parts, which you could tire of.
“It’s not something I want to keep doing over and over again. And I got a lot of stick about it, too. Playing a prostitute doesn’t go down well with everyone, surprisingly. But the role took me into the American market, which is fantastic.”
Next stop the US, then?
“Well Laurence and I would both consider it and there do seem to be more roles there,” she says. “But I love it here, I love England and I can’t imagine moving permanently. It’s this time of year that you think there’s nowhere more beautiful in the world. There are brilliant things about LA, but I’m a real sucker for home.”
