The former Sugababe Siobhan Donaghy is a bit worried about her parents seeing her in the West End revival of Rent; she’s playing a stripper.

“I am pretty much down to my underwear for much of the show,” she sighs, “so I’m dreading my father coming to see this. Actually, my manager’s going to be just as shocked. I’ve been with him for six years and he’s seen me go from having zero confidence and stage fright into becoming a completely different person. So this overtly sexual act is going to be quite a shock for him, too . . .”

Rent is a rock musical that sets Puccini’s La Bohème in New York’s preGiuliani East Village, swapping TB for Aids, painters for film-makers and poets for rock singers. Written by Jonathan Larson (who died the day before the show’s off-Broadway premiere in 1996), it has been a huge success in America. It’s played at Manhat-tan’s Nederlander Theatre since 1996, making it the long-est-running musical on Broadway; it’s spawned several successful touring productions and established a young subcul-ture of obsessive “Rentheads”.

Surely, for Donaghy, there must have been a less demanding way of conquering her stage fright?

“I never get stage fright any more,” the 23-year-old singer replies. “It used to be terrible. To be honest it was because there were some very unsup-portive people around me who didn’t seem to believe in me and thought I was crap, which is a bit of a hindrance.”

It was on a live tour of Japan in 2001 that Donaghy decided she had had enough of the Sugababes roadshow and quit the band, leaving her fellow founder members Mutya and Keisha behind. Donaghy was later diagnosed with clinical depression.

Since then she has been a bit of an oddity in the world of pop – a gothy, feisty, self-taught maverick, in love with Kate Bush, the Cocteau Twins, Arcade Fire and the novels of Milan Kundera. She toured under the nom de plume “Shanghai Nobody” (an anagram of her name), and released intelligent avant-tinged pop. Sadly her last CD, Ghosts, sank without trace, despite some rave reviews.

Donaghy cancelled her live dates and was pondering her next move when she got a call from William Baker, the maverick stylist who is perhaps best known for pouring his chum Kylie into gold hot pants. Baker was directing a new “remixed” version of the Broadway musical Rent, and was interested in hiring Donaghy for the lead role of Mimi.

“I then watched the film and thought they must have made a mistake,” she laughs. “I loved the show but the music wasn’t really my kind of thing. More importantly, I didn’t look anything like Mimi!” Mimi is usually Hispanic or black, being played in the film by Rosario Dawson and, for a while on Broadway, by Scary Spice Mela-nie Brown. So Donaghy – a milk-bottle-white Irish redhead from Eastcote, West London – seemed an odd choice.

“The thing was that William was very keen to revamp the whole show. For Mimi they were looking for more of a Nicole Kidman from Moulin Rouge,or a Tra La La from Last Exit to Brooklyn. She’s no longer a stripper in a sleazy bar exactly, she’s more of a burlesque performer. She’s someone who wears a happy mask, but it’s fairly obvious early on that she’s a tragic character and we are going to watch her gradual demise throughout the show.”

She admits that it has been a steep learning curve. Although the eight-year-old Donaghy was an all-England champion Irish dancer, she has no formal dance or drama training, and “very nearly collapsed” after the first week of rehearsals. “It’s a ‘hard sing’ but it’s also a physically demanding role.”

In Britain, it also faces a challenge of another kind. Although the show first ran for a respectable 18 months in 1998--99 at the Shaftesbury Theatre, it failed to inspire singalongs or whooping in the aisles, as in the States. This is partly because British audiences were never that sympathetic to the characters – a gang of middle-class Bohemians, squatting in what looks like prime Manhat-tan real estate, rising up against an entirely reasonable landlord who has the cheek to request a year of unpaid rent (they even kill the landlord’s dog). Also, the songs, which veered towards slacker rock and smooth R&B, had little resonance here.

This production aims to address some of those issues. William Baker and his music director Steve Anderson have shifted the songs away from adult-oriented rock towards Euro-friendly pop (“less Jon Bon Jovi, more Kylie”, says Donaghy). It’s still set in New York, but several of the English principals – including Donaghy’s Mimi, Leon Lopez’s Angel and Denise Van Outen’s Maureen – retain their accents. “Wil-liam wants to make the characters more real,” says Donaghy.

The move from pop to musicals is generally regarded as a one-way street – pop stars often find it difficult to return to the music business after a spell in the West End. Does she envisage coming back?

“We’ll have to see,” she says. “I have a five-album deal with Parlophone, so I’m still hoping to write and record and tour again. But maybe I’ll love this so much I won’t want to go back!”

Rent, Duke of York Theatre, St Martin’s Lane, London WC2 (www.theambassadors.com/dukeofyorks 0870 0606623), from Mon

HOOFING IT

Kelly Osbourne Plays the prison matron Mama Morton in Chicago, once Alison Moyet’s part.

Stephen Gately After Chitty Chitty Bang Bang and The Wizard of Oz, the Boyzone star is touring in Godspell.

Jason Donovan Starred in Joseph and the Amazing Technicolor Dreamcoat before Chitty Chitty Bang Bang and Sweeney Todd.

Marti Pellow The Wet Wet Wet frontman has played Billy Flynn in Chicago in London and Broadway.

Darius Danesh The Pop Idol contestant has appeared in Chicago and Guys and Dolls.

Cliff Richard Began a year-long run in 1995 as the lead in his own musical Heathcliff.

Explore Music

• Proms

• Festivals

• CD Reviews

• Live Reviews

Editor's choice

• The End: the worst movie endings ever
• Introducing The Times Proms Podcast
• Heath Ledger tipped for Oscar