Actress Billie Piper, who’s back playing Belle in the final series of Secret Diary Of A Call Girl, tells Susan Griffin that after three years of prancing around in undies she is super-confident doing saucy scenes.

BILLIE Piper’s not feeling well and she’s blaming her two-year old son Winston.

“When you have a child, it’s really hard to shift illness because they’re continuously bringing it into the house,’’ says Piper, 28, coughing.

Even on an off day, though, she manages to look glamorous in a short T-shirt style dress, over-theknee boots and a long woollen cardi.

She’s shorter, more petite, than you’d expect and even the wide mouth and strong brows seem softer in the flesh.

Winston aside, it’s understandable Piper’s feeling exhausted. She’s just finished a seven-month shoot filming the fourth and final series of Secret Diary Of A Call Girl – the successful TV show based on the diaries of real-life escort Belle De Jour. Her performance as Belle has been applauded, but when it was first announced in 2007 that Piper, former pop princess turned Doctor Who assistant, was to play the high-class hooker, people were up in arms.

‘‘Outraged,’’ says Piper, sipping a cup of tea. ‘‘I didn’t think it would be as shocking as it was, and I didn’t really think that me being in it would be shocking. I just thought I’m an actor and it’s just acting.’’ She admits the furore hit her hard.

‘‘There are loads of women out there who have a horrid time of it – prostitution – but women go out and have casual sex and talk about it endlessly and Sex And The City is a really good example of that. That show’s sometimes quite shocking and yet people also applaud it, but as soon as money changes hands then that changes everything.’’ IT was the chance to address these double standards that interested Piper in the first place. ‘‘To play a prostitute who has chosen to do it, I find all of that quite interesting.’’ Given Belle’s profession, it’s little wonder Piper’s had to spend the majority of her time in compromising positions – as she puts it ‘‘endlessly prancing around in your knickers trying to be sexy’’.

She’s now so comfortable doing sex scenes that at times she’s had to remind herself that the actors cast as her numerous clients can require a little cajoling. As for preparing to strip off, Piper says she works out a bit, adding: ‘‘I also really watch what I eat when I’m filming so I don’t have those moments where I think ‘I can’t do this’ because I don’t feel physically confident enough.’’ The final series may, as she says, be less about flesh, but the client requests are no less shocking, with Adult Baby and Count Dracula among the upcoming scenarios.

Even after three years, Piper admits to being ‘‘a bit shocked’’ when she first reads the script. ‘‘I just think, ’Well that seems a bit far-fetched’, and then I meet with the people who are telling their stories and it would be rude to go, ‘Well, that’s a bit much, don’t you think’? It’s someone’s life, so you can’t suddenly be sitting there going, ‘I think you need to go to a doctor’.’’ The sense that the series has explored all the potential client/escort avenues is largely why it’s been decided to bring Belle’s tale to an end.

‘‘I think we’ve pretty much been everywhere with the stories and as that’s at the heart of every episode, you wouldn’t want to exhaust it to the point of just complete ridiculousness and seediness,’’ says Piper.

Since the first episode, viewers have witnessed Belle’s attempt to keep her professional and personal life, including her potential relationship with best-friend Ben, separate.

But in this final series those two worlds merge. ‘‘It’s really honest and dramatic and I think it ends in the way it started – unapologetic and shameless.’’ So what’s next for Piper? She’s not yet 30 but has managed to cram more than most into her life.

Born in Reading, she came to prominence as a 15-year-old pop star after being spotted on a Smash Hits campaign. Her marriage to Chris Evans in 2001 raised eyebrows due to their 16-year age gap. After their amicable divorce six years later, they have remained resolutely good friends.

Evans even reportedly hosted the wedding reception when she married Winston’s father, Laurence Fox, on New Year’s Eve 2007.

Professionally, she’s made the seemingly smooth transition from singing to acting and has received rave reviews for her performances on stage in Treats, where she met Fox, and on screen in the likes of The Ruby In The Smoke, Mansfield Park and A Passionate Woman.

‘‘I think I’ve just chosen things that have interested me and then kept trying new and different things,’’ she says. ‘‘That’s the only thing that really keeps me interested really. It has worked out well and I can thank Doctor Who for all of that really. It was wholly responsible for giving me a great opportunity.’’ Given the success of Secret Diary in America, you’d think Piper would have her sights set on the US. ‘‘I keep thinking about it, but then I like England,’’ says Piper, who lives in a cottage in West Sussex. ‘‘To be out there with a baby and to do seven, eight auditions a day is just not massively appealing at the moment.

‘‘I just want to do something radically different and I don’t know what that is yet. I have done a lot but there are so many more things to do.’’ * Series four of Secret Diary Of A Call Girl begins on Tuesday, February 1 on ITV2

Belt up like a celebrity

TOP celebrities are helping the fight against poverty by donating their coats to the Wrap Up Against Poverty winter coat auction being held by Elizabeth Finn Care.

Look as uber-trendy as Sienna Miller in her signed Anya Hindmarch for Barbour jacket which she has generously donated. Or follow the military trend in Christine Bleakley’s ultra-chic olive green coat with ontrend military detailing from Monsoon Fusion, or Tamara Ecclestone’s sophisticated black military style coat with gold buttons and frill from Daslu Sao Paulo.

Fearne Cotton has donated a funky faux fur hooded grey leopard print coat from her Very range and fashion house Burberry are offering a VIP shopping trip and the choice of one of their iconic trench coats up to the value of £800. Fashion’s favourite Dame, Vivienne Westwood, has donated a pair of Melissa Lady Dragon Cherry-Green shoes.

There are 13.5 million people living below the poverty line in the UK.

Elizabeth Finn Care aims to raise money to help buy more people in financial need essential clothes.

Britain’s Next Top Model finalist Joy McLaren is shown modelling two of the donated items above.

Malcolm Tyndall, Director at Elizabeth Finn Care, said: “ By supporting the auction you could not only win a coat worn by one of your favourite celebrities but you will also be helping us to ensure people in financial need have warm clothes to wear during the winter months.”

* The auction begins on eBay on Monday, January 31. Visit elizabethfinncare.co.uk