Billie Piper is famous for being the pop star married to an older man. Now she's playing a budding pop singer married to an older man in a new version of Chaucer's The Miller's Tale.

Piper reveals to Steve Pratt that she started out as an actress and has no pop comeback plans Making her acting debut in BBC1's ambitious new adaptation of Chaucer's The Canterbury Tales is a big deal for chart-topping singer Billie Piper. "What people don't really know is that I started out acting," she says. "I left home in Swindon to go to Sylvia Young's theatre school in London when I was 12 because I'd applied for a scholarship. I needed to act 24/7, all week, just throw myself into it. At home, just one class a week wasn't really doing it for me.

"Then the pop career came along. Although, at the time, I realised it would take me away from the acting, I felt it could also open a lot of doors for me, which I think it has."

Pop sensation Piper, who's married to DJ turned producer Chris Evans, stars alongside James Nesbitt, Dennis Waterman and Kenny Doughty in The Miller's Tale - the first of six of Chaucer's tales to be updated for a modern audience.

Cold Feet star Nesbitt plays Nick Zakian, a smooth-talking stranger who arrives in a karaoke pub in a Kent village claiming to be a talent scout. He promises karaoke queen Alison (Piper) fame and fortune, although her pub landlord husband John (Waterman) and effeminate barber Danny (Doughty) stand in the way. To research her role, Piper joined wannabe singers in London's karaoke pubs. "I used to sing karaoke all the time, including La Bamba with my dad, which was always hysterical," she recalls. "But I'd not done it for ages, so I dragged my friends round all these pubs to get a feel for what it's like."

Fans of the singer, whose hits included Because We Want To and Day And Night, will hear a different sound when the 20-year-old takes the mike at the karaoke machine. Her voice has changed, thanks to special training from Fame Academy's Carrie Grant.

"I didn't want to go on screen and do something that everybody already knew about," says Piper. "It would have been hard to get into character if I was singing with a voice that I'd sung with for ever. That's why I got in touch with Carrie. She's an amazing woman. Working with her was a wonderful experience, she can sing with so many different voices. She helped me changed my technique. I wanted Alison to have a voice that belonged to her and nobody else."

As well as singing, Piper has several saucy moments in The Miller's Tale. In one, writer Peter Bowker re-invents the famous scene where Alison tricks a young suitor into kissing her bare behind. She admits to being quite daunted by the prospect, but director John McKay drew a storyboard of how the whole scene would be shot and how it would look.

"He really wanted to make me feel at ease," she says. "So you don't see my arse full on. It's poor Kenny Doughty who got the whole shebang. But that won't be seen."

She also has sex scenes with Nesbitt, and knows that, as a viewer, you always want to ask if it was weird doing them, did they get turned on, and what does your real life partner feel about it. "But when you're doing it, you've got these pieces of tape round your breasts and the ugliest tanned thong on, and all the lighting and sound," she says.

"It's just not sexy, which makes it easy to play sexy, and just go for it in the mindset of the character. I can imagine that in those situations, if you don't suspend reality, it can really mess with your head, because it's not real.

"My husband understands that it's my job. That's the good thing about being married to somebody who understands the technicalities. "Having been married for two years, I'm more domesticated now and I love it. I know it sounds a bit of a cliche, but when you come home and just do some jobs around the house, it does just bring you back to Earth because after filming you're so hyper.

"You have to come back down, otherwise you don't sleep, you grind your teeth and just burn yourself out."

Speculation that she's about to return to her pop career isn't accurate, she insists, and she's glad to have turned her back on that life. She found it too fast-paced.

"If I'd carried on I would have missed out on so much real life, and I'm so happy with acting. It gives me the time and freedom I need in life. When I finish a day's work I can still get some time at home to make some dinner, watch a bit of TV, have a cup of tea in bed.

"I love cooking. I hated it before I met my husband. He taught me all I know about the kitchen. I now love making pasta sauces, stews and baking - although I'm still working on that.

"I love hanging out with our dogs, just being part of proper things and it's these things that help me to act because, if you can't observe real life situations, then how can you go out there and try to become somebody else?"

- The Canterbury Tales: The Miller's Tale is on BBC1 on Thursday at 9pm