SCOTTISH-born actress Simone Lahbib, best known as former Bad Girls prison governor Helen Stewart, has moved over to the dark side. At least, that's how she thinks of the character in the new London-set underworld drama Family.

As Jacqueline, known as Jacks, she's the only daughter of Ted Cutler, one of Britain's most notorious villains and nicknamed The Guv'nor (played by David Calder). He runs the family firm, which deals legitimately in gaming machines, but whose real business is crime.

His two sons are played by former EastEnders actor Martin Kemp and Jamie Foreman, whose father Freddie Foreman was a renowned South London gang leader.

Lahbib sees Jacks as a mix of both brothers - the dark, edgy, dangerous street of one and the sensibilities and lightness of the other. "She might look all girly, but underneath those tight jeans, she's a girl with balls," says the actress.

"What I love about her is that her strength shouldn't be underestimated. She's a force to be reckoned with. She's got so much going on, including a mean streak.

"She's a feisty girl, but a real survivor. The flip side, and what's interesting about her, is that she's a lost soul. She's got a lot of time, a lot of money, but nowhere to put her energies and therefore no purpose.

"A lot of the characters I play are women with a vulnerable streak, which Jacks certainly is, but she's also fun, so I've had lots to get my teeth into." The actress has nothing in common with Jacks, except maybe that they're both good at keeping secrets and shopping. "Forgive my outlandish analogy here, but I see her as a bit of a Darth Vader character," she says.

"She's denied love in her life and, as a result, crosses over to the dark side. Whereas, in contrast, I like to see myself as a sort of Yoda character, that underneath the cute little exterior lies a profoundly wise old soul."

The secret of Jacks power is that she's the keeper of a family secret. Not that she'd break the laws of her world or womanhood and not protect the family, above all else.

"All she thinks she wants is to have that princess fairy tale - meet her prince, her knight in shining armour, fall madly passionately in love and live happily ever after. Why else spend a fortune on Gucci and grooming? Unfortunately, her brothers have very different ideas about her choice of partner," she says.

Lahbib, born and brought up in the Scottish town of Stirling, needed to cultivate a London accent for the role. She found it fun to do and easy to get as she was surrounded by the accent on the Family set.

"I only ever needed to spend five minutes with Camille Corduri, who plays Joey's wife, and I'd come over all 'apples and pears, cor blimey guv'nor' and, before I knew it, I was Barbara Windsor in a Carry On film," she says.

"Whereas I found the straight, middle class English accent I did for the character I have just played in another TV series, Guardian, a lot harder to do - very controlled and much less colourful."

She played governor Helen Stewart in the first three series of women's prison drama Bad Girls, so Jacks represents a distinct change of image. Sub-consciously, she supposes, she was trying to find a role that was very different.

As an actress, her aim has always to do good varied work. She always tries to do one theatre job a year, most recently appearing in a play with Pete Postlethwaite at Manchester Royal Exchange. She also filmed an episode of BBC1's Judge John Deed.

The joy about being part of Family was that she found the characters and story made it compelling reading. She's sure the series will make equally compelling viewing, and that people will recognise situations.

"When Jacks gets drunk and dances around, she makes such a scene and is so tragic. It'll be painful to watch, but then we've all been there. Or is that just me?".

Family begins on ITV1 on Monday at 9pm