Dervla Kirwan plays the character Davina Bailey in Material Girl...

Hi Dervla. Can you tell us about your character?

Davina isn't a very talented designer, she's insecure and has to delegate everything to her designers and find time to keep her empire going.

She's good at manipulating the world she's in and that's why she's successful. At the same time Davina is a self-made woman, totally creative, an individual with a desire to control everyone and everything in her empire.

Would you go so far as to say that she's villainous?

Yes, she is, because the stakes are high. I've chosen to play her as motivated by greed and, when that's what drives a person, nothing will stand in their way.

She's put 20 years of her life behind the business, given up her life to it. She has no family, no relationship. Everything is her work and she's not letting anything stand in her way.

Were you inspired by any real or fictional characters?

I watched Lagerfeld Confidential, which was such an insight into the daily life of a maverick designer. I've never met any of these extraordinary, eccentric people, so it was really useful, they are very creative and under enormous pressure.

Can you describe the Davina Bailey look?

The look is an amalgamation of icon and siren, she's like a female Karl Lagerfeld with attitude, Mrs Robinson meets Deeta Von Teese. She's always dressed in black, very 1940s Hollywood, Joan Crawford with a twist.

She has quite a bit of control over the other characters?

I'd agree and it really makes her enjoyable to play. She's clever, always ahead of everyone.

If you look at the set for her design studio, it's all glass, which is very much a metaphor. It looks like a goldfish bowl and, because I'm always dressed in black, it adds this black widow spider quality to my character.

Is it much more fun playing a bitch?

Yeah, I think it is, of course. She's not a pantomime villain either, which is always a fear, because it's not as simple as that in real life.

How did you get involved?

I liked the idea and I thought this is something I've never seen before. The scripts were good, with interesting characters coming through. It felt to me a bit like a fairy tale.

Now it comes to this stage of my career when I get to play the wicked witch all the time. You know you start off with Cinderella and then you end up playing the stepmothers.

Are you interested in fashion?

Yes, very much. I don't think there are many people who aren't, particularly in this business. My favourite designers are Stella McCartney, Balenciaga, Karl Lagerfeld, Chanel and Givenchy, but I wish I had loads of money to spend on them.