Austen powers: How Pride and Prejudice got a twist of Dr Who

The answer is Lost In Austen, a major four-part comedy drama which premieres on ITV1 this week. It's scripted by Guy Andrews, who cheerfully admits he is mangling the nation's favourite book, and stars 26-year-old Jemima Rooper who is more used to appearing in cult programmes such as Channel Four's As If and Sky One's fantasy drama Hex, where she was cast as a lesbian ghost.

Rooper plays Amanda Price, a sassy 21st century Londoner who finds in Jane Austen's novel all the romance her burping slob of a boyfriend fails to provide in real life. More to the point, she also finds in her bathroom a portal into the Bennett household. Elizabeth Bennett has opened it and clambered through and is playing with a light switch when we first meet her. Don't laugh: it could happen.

Amanda crosses the threshold the other way to see for herself what the fictional house looks like, but as she does the door clicks shut behind her. So now she's trapped in Pride And Prejudice wearing jeans and a very inappropriate top. Realising she is at the start of the book she knows what's supposed to happen next - but that doesn't stop her getting drunk and snogging Mr Bingley. Unsurprisingly, the stern Mr Darcy doesn't take to her at all.

"It's genius," Rooper cackles, flashing a tattooed right wrist as she scrumples her dark hair. "I think what Guy has achieved is that he's got all the elements that people love about the novel Pride And Prejudice, or even the BBC adaptation of it, but then he's dealt it this very witty twist. He's kept all the nostalgia, all the affection you have for Mr Darcy and Elizabeth, but then he's made it up-to-date and punchy and interesting."

We are talking in the green room of London's National Theatre where Rooper is currently appearing in Rebecca Lenkiewicz's play Her Naked Skin. It's another lesbian role, her fourth if you don't count George in The Famous Five, made when she was just 13. Exactly how punchy Guy Andrews has made Lost In Austen is evident in one telling early scene. Thinking she may actually be in a very cruel reality TV show, an angry Amanda flashes Lydia Bennett, who has crept into bed beside her in the night.

"What have you done to yourself?" asks the wide-eyed Lydia, staring at the naked midriff. "Oh," says Amanda, looking down. "That's called a landing strip' in London. Pubic topiary."

Andrews had to fight hard to keep that line in, and there were a few more the ITV producers deemed too close to one bone or another and which were ruled through with the censor's blue pencil. But it sets the tone for a production which, along with Andrew Davies's erotic adaptation of the Sarah Water novel Affinity, proves that the broadcaster is serious when it says it wants to increase its appeal to younger viewers and up its game where high-profile drama is concerned.

It was Davies, of course, who scripted the BBC's now legendary 1995 adaptation of Pride And Prejudice and he will be pleased to see there are plenty of Colin Firth jokes in Lost In Austen. There's also a stellar cast which includes costume drama veterans Hugh Bonneville, Lindsay Duncan and Alex Kingston.

So Lost In Austen is rude, cheeky and funny - but does it treat its source material with enough fondness to ensure that only the sniffiest Austen fans will wrinkle their noses in distaste? Just about.

Watching it, however, you realise it's going to be hard to take any future adaptations of the novel seriously. It's as if this knowing, slightly mocking and entirely self-referential drama has finally burst the costume drama bubble. If it has, it's not before time, says Rooper.

"These great big lavish costume dramas are our favourites because they get more money spent on them, they have great casts, lovely scripts and high production values," she says. "But we've seen all that. We saw it years ago and now everything's just another remake. What's nice about this is that you've got characters you know and love but in completely different circumstances."

Nevertheless she was as taken with Colin Firth as the rest of the nation's women. "I think I was, yes, vicariously through my mother," she laughs. "I think I was a bit young to quite get it but I pretended I did. But he is brilliant in it and I still watch it." And how does Elliot Cowan, her own Darcy, compare? "Elliot's a very, very handsome young man," she grins.

Although familiar to those whose viewing tastes take them to the more peripheral television channels in search of hipper, edgier fare, Jemima Rooper is relatively unknown in the mainstream. That will change now, though by her own admission she is as far from the blonde, doe-eyed, ringlet-haired heroine of the traditional costume drama as it's possible to be.

For a start there's the Scorpio tattoo on the wrist, inked when she was 19. Then there's the thick hair, which for Hex was hacked into a spiky lop-sided mullet. It's a little less severe looking today, though equally unruly. Finally, there is the wide mouth, the cackle, the revelation that she is fond of clowning around and has always been a bit of a tomboy.

In the past her look and her character have made auditions difficult and finding good parts hard. "I just know that if I walk into an audition I won't look right," she says. "It's not like I think I'm a hideous troll or anything, it's just a question of not being the most beautiful. A lot of it is decided as you walk through the door. I've got a lot of very beautiful young friends who are doing very well and I know if I was a director and they walked through the door I'd be like Wow! Yeah!'."

Given her propensity for landing parts with a heavy sapphic element to them, I'd have thought "wow" and "yeah" were words she heard a lot - it's certainly true that her character in Hex had a slew of internet admirers for that very reason. But in a casting environment in which good female parts are hard to come by she has too often been relegated to the supporting roles.

She rubbed shoulders with Scarlett Johansson and Hilary Swank in Brian De Palma's 2006 film The Black Dahlia and featured in the Golden Globe-nominated Britflick Kinky Boots, but Lost In Austen is the first time she has been given the opportunity to dominate a production. "Being the lead and being in every single scene is not something I've done before," she admits.

But it's also given Rooper the chance to display her talent for comedy to a mainstream audience. The script itself is witty enough - "Even the stage directions are funny," she says - but it's her pitch-perfect performance, equal parts bamboozlement, embarrassment and amusement, that gives Lost In Austen its crowd-pleasing oomph. "It's weird," she says, "because the couple of jobs I did when I was 16 were very serious dramas where I was playing heroin addicts and stuff like that. They were heavy issues and that's what I assumed I was good at and could do."

Now, though, she is not so sure. Comedy, it seems, may be her natural metier: indeed the time she spent in As If saw her character, Nicki, change from serious to quirky, partly through her own ministrations.

"That environment was an incredible one in which to make television because you could have a lot of input if you wanted it and there was a couple of us who did," she explains. "So through ideas I had which were just stuff that came naturally, we all started getting a bit zany. Then they started writing for that and Nicki became a completely different character. She turned into a bit of a clown, which was also the sort of human being I was growing into."

The team that wrote As If then went on to create Hex, a supernatural story set in a boarding school and dubbed "Buffy on a budget" by the critics. The character of Thelma was written specifically with Rooper in mind and, though Hex was cancelled after two series, it was screened in America. To this day, Rooper still gets fan mail from random cities across the continent.

"I once got a text message from a friend in New York saying I've just seen your face on a bus in Times Square," Rooper laughs. "Because of the Britishness of it and because of the subject matter it just filled that little hole that Buffy fans wanted filling."

Rooper is not the only member of the Hex cast to be hitting the big time this year. Her co-star Christina Cole is also in Lost In Austen - she plays the bitchy Caroline Bingley - while Zoe Tapper stars in Affinity. Meanwhile, Rooper's close friends Gemma Arterton and Tamsin Egerton are also making waves. As well as playing Elizabeth Bennett in Lost In Austen and the lead in BBC1's forthcoming dramatisation of the Thomas Hardy novel Tess Of The D'Urbervilles, Arterton will soon be seen on the big screen in the new James Bond film Quantum Of Solace. Egerton, who starred in the recent St Trinians film, will appear in ITV1's upcoming drama Octavia, based on a Jilly Cooper novel.

And what next for Rooper? She is off to Los Angeles, she says, but only on holiday. Before Hex started filming she did decamp to California to endure the rounds of auditions but grew tired of "being fed a lot of chit-chat all the time. It gets exhausting after a while. And I got embarrassed to say I was an actor because everybody is an actor, everyone's got a script for you to read. It's sounds like a cliché but it's really true."

No plans to move there full-time, then? "I couldn't," she says, "and if you want to make a career over there or you're aiming to get work you have to be there the whole time. My agent and I kind of fell out over that because I was always running back home."

It's been a busy year to date and she is tied to the National Theatre until well into the autumn, by which time Lost In Austen will have either flopped or soared. My money's on the latter. After that, she waits for the phone to ring, though there's still one more chance to glimpse her on screen before the year ends. "I've got an episode of Poirot coming out soon," she laughs. "And I'm not a lesbian this time, which is a nice change."

Lost In Austen starts this Wednesday, 9pm, ITV1