Sian Brooke says she loved playing a character that was a 'superbitch'.

Hi Sian. Who do you play in Not Safe For Work?

I play a woman called Martine McCutcheon - not the Martine McCutcheon - this one is quite a formidable character. She's a powerful businesswoman, and she is brought in from the London head office to shake things up a bit in Northampton, to refine and streamline! She's fantastic - I so enjoyed playing her. I'm often cast as a victim so it was really enjoyable to play a strong woman, some might say a superbitch!

Would you describe her as the villain of the piece?

I think probably, on first impressions, you would say that she was. But as with all villains, when you're playing a character who might be perceived as villainous, you try and find something in there that you can latch on to, a vulnerability that makes them human.

As with all of us, she's got her own flaws and insecurities, and that's what, I think, in the end, made her so enjoyable to play. On the surface she's quite ballsy and bitchy, she's definitely not there to make friends and yet as the series unfolds, you see she might not be that strong.

What is it that's such fun about playing a baddie?

I think part of it is you get to behave in a way you would never normally behave. She's very definite in what she wants and needs, and it's great because she's really ballsy in the way she goes about getting.

The writer has created some very strong female characters, hasn't he?

Yes, It's very female-led, a real breath of fresh air. DC Moore has created some incredibly complex, well-rounded characters. Katherine is a brilliant character and what Zawe's done with her is really exciting - so many women, myself included, can absolutely relate to her. The genius of the writing is that DC has created such a spectrum of different women at work as well as exploring their personal lives.

There's a very natural feel to a lot of the dialogue. Did you improvise much?

We did little bits. His writing was so good, though. When I first read the scripts, I thought "I've not read anything like this in a long, long time." It's hard to place the writing, in terms of whether it's drama or comedy. It's a really fine line. One minute you'll be laughing your head off, and the next, you'll be in floods of tears.

Each of the characters has their own voice. Sometimes you'll read scripts and every character sounds the same. I think, in this, they all have a distinct way about them. There are little bits of improvisation, though. Sacha is a genius at improvisation - and he and Zawe would riff of each other... a joy to watch. So I think it's a bit of a mixture of both.

The show doesn't make working in an office look like a great deal of fun. Have you ever had an office job, and if so, how was it?

I have. I shan't say exactly what it was, because I don't want to offend the people that worked there. But the highlight of the day was "What are we going to have for lunch?" ...