Jennifer Ellison is back. And this time she's acting for her life. Really. Look at her there, in the first-act climax of the smart new Britflick comedy-horror The Cottage. She's doped up and lifeless, trussed up in ropes and gags, a helpless kidnap victim in low-slung tracky bottoms and tight microtop. But wait! No! She's waking up, and she's loud and aggressive! And what's this? She's kneeing the hapless kidnapper Peter (Reece Shearsmith) in the groin! She's dropping him to the ground and, still bound and gagged, butting his nose into a bloody pulp. “I just broke your f***ing nose with my hands tied behind my back,” she growls in guttural Scouse, gag yanked down, lips curled in disgust. “So what does that make you?” Welcome, boys, to the new Jennifer Ellison. Ogle at your own risk.

“But I found that so difficult,” she says, as she recalls the rage, and the cold nights on set in the Isle of Man when this 24-year-old men's mag icon and Brookside babe got deeply in touch with her inner demon. “I found it hard to be so horrible, so abusive and so vulgar,” she says. “But Paul [the writer and director Paul Andrew Williams] just came up to me and said, ‘I want you to be like a wolf who's been caught eating a body. I want that glare!'”

He got the glare, and the rest, in a broad and amiable gore-splattered slapstick farce that turns out to be the smartest thing that Ellison has done in years. For here, as the victim turned aggressor, she single-handedly inverts a decade of damage done in the glossy name of self-promotion and B-list shenanigans. By gamely playing a ball-busting harridan she has somehow thumbed her nose at her old self. But still, there are doubts. “Every time I read a review and it says, ‘Jennifer Ellison is trying to prove that she's more than a Nuts magazine babe,' I go, Why?!!!” she groans. “I've done six years on a soap, been in a Hollywood movie [Phantom of the Opera] and on the West End. But why do people just remember me for Nuts magazine?!”

Why indeed? Was it her sunny charm? Or was it the way that her baby face, thundering breasts and hooker lingerie forced her into that discomfiting gap between teenage innocence and slatternly desire (men, they are just so creepy). Either way, she did her first magazine shoot, for GQ, aged 15, under the heading, “The Lolita Syndrome”. She was, she says, naive and gullible.

“When I think about it now, Brookside really shouldn't have made me do it,” she says. “I was an actress, and I think that they exploited me.”

It could have been a different story, about an alternative Ellison. This one was a ballet dancer growing up in Liverpool with grit, perseverance and a cabinet full of trophies. She started at 3, and won the Junior International Ballet Championships five times. “While my friends were drinking cider at bus stops I was doing ballet every night.”

But then on a whim she auditioned successfully for Brookside and the role of Emily O'Leary, a teen tearaway with a penchant for trashing cars. Audiences loved her spice, the show adored her ratings and photo-shoots were arranged.

But Brookside killed the ballet, and clubbing took its place. She partied hard, she lived the life, and she dated a famous footballer (Steven Gerrard). But cover shoots have a price, and when your breasts are out your private life is ours. Her biological father, gone but not forgotten, sniffed a payday. “My own real dad sold a story about me,” she says. “And my little sister didn't know that she was my half-sister. She went into school and people were going, ‘I knew you didn't look like her!'” Her family - mother Jane, stepfather Peter, and sister Jemma - were distraught.

And still, she says, this same father, this biological one, has driven her career, unbeknown to him or to anyone around her. Her need for recognition, she says, is “me, subconsciously, trying to prove him wrong. I'm trying to say, Look! You made a mistake!” She smiles at this, awkwardly, and sadly. She says that this feels like therapy, and that she owes me money.

The actress says that she is ashamed of nothing that happened post-Brookside. That it all, everything, the shoots, the West End Workout DVD, the reality TV exposure (Hell's Kitchen and Jennifer Ellison Does Thailand), the role on stage in Chicago and the inchoate music career, it all had a point. The Phantom of the Opera director Joel Schumacher spotted her singing on GMTV and declared he wanted her for his movie. “It's all connected,” she says, drawing a line between spreads, singing and acting.

And yes, acting is where she is now, and where we leave her, becoming more credible by the minute, proving them wrong in West End revivals such as Boeing Boeing last year, and flashing, for once, her real chops, in The Cottage. She's just auditioned for a “huge Walt Disney movie” and is already doing the post-Cottage casting rounds. She has also cracked down on media exposure - doesn't do photo-shoots, hasn't been in the tabloids since her break-up with the sunbed salesman Tony Richardson. She doesn't go out either, and would rather be sitting on the couch in her Liverpool home, eating Chinese food and watching junk television, than partying in London with the best of the worst.

She has thick skin, she says, and nerves of steel, and she knows she might need them. For the possibility of a career-scuppering photospread is always just around the corner. “There are so many pictures of me out there now,” she says, half-shaking her head. “I haven't done a shoot in three years and still I'm on the cover of Nuts and Loaded.” She says, because of this, it all might end tomorrow. And if it does, she says, she'd walk away. But you know that she won't. That she's driven from deep within, and that she'd be back the next day, brighter and better, with a wider smile and a tighter top, and a head-butt reserved just for you.

The Cottage is on general release from Mar 14

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