For some years Diane Parish has been talking about how broody she is. But as the heavily pregnant actress - best known for her two-year stint in The Bill as DC Eva Sharpe - sits down to be interviewed it's obvious she won't be repeating herself.

''Yeah, I'm over the broodiness now,'' she laughs.

The 36-year-old is due to give birth in September. It's her first child, with her partner of over four years Sebastian, a technical manager at a DVD company.

''It's due on the 13th,'' she says. ''That's not a Friday is it? I hope not. I'll get one with two heads,'' she laughs.

''We don't know the sex yet, we didn't want to. We want all the surprises to happen at the right time.''

She's not worked for a while due to the pregnancy. She filmed a guest role for the forthcoming series of BBC drama Waking The Dead during her first trimester (''I'm using words like trimester like I'm really experienced,'' she says.), but has since, as she puts it, ''put her feet up''.

''It's been a good pregnancy,'' she says. ''The first part of it I was quite sick and tired and became quite ill. The same happens in the last part so I'm feeling like that now.

''The worst part was feeling sick and tired when I was working on Waking The Dead. I would just fall asleep on the train on the way to work, just nod off. Then I got loads of energy in the middle and now I'm back to tired again.

''It's nice though, it's got to be. I wanted it to happen.''

It's not all rest and relaxation for Diane however. She has a new show to promote, albeit one she filmed at the beginning of last year. When she left The Bill in January 2004, she took her character DC Eva Sharpe straight to the second series of that show's spin-off - Murder Investigation Team.

But although she and the rest of the cast and crew finished filming on the series about a year ago, it's taken until now for the series to make ITV schedules.

''I left directly from one to the other because Eva left Sun Hill as if she was going to MIT,'' says Diane. ''But it hasn't worked out like that on screen.

''It is a little bit frustrating that it's taken so long. I've played so many different characters since I filmed MIT, it's a bit weird talking about it now.''

What Diane also found strange was playing the same character in a new show with a completely new cast and crew.

''It was slightly odd,'' she says. ''But I wanted to treat it like a new job and that's how it was treated by everyone else. I wanted to treat being Eva in MIT as a new thing for me and a new thing for Eva. I took the old head off and put a new head on, kept what was necessary.

''And I was looking forward to working with Lindsey Coulson as well. That was a real attraction for me because I remember her being talked about during my EastEnders days. I always liked her work and thought, she seems to be a bit like me in the way we think and how we are.''

Diane first crossed paths with Lindsey, who played Carol Jackson in EastEnders for four years, when they both worked on the drama Clocking Off in 2001. But it's surprising the pair didn't meet earlier in their lives.

''We've got weird connections in terms of background,'' explains Diane. ''We both grew up in the same area - Edmonton in London, and she had my horrible old maths teacher Mr Morgan. We both hate maths because of him.

''Then we ended up buying our first flats in the same road, in Walthamstow. I remember we just got talking, it was about five o'clock in the morning on a bus on the way to Wigan to do Clocking Off, and we found all these things out. It was uncanny.''

In the first episode of the new series of Murder Investigation Team, Diane and Lindsey's alter egos don't get on as well. Eva has to hit the ground running as she struggles to prove herself to her hostile new boss DI Trevor Hands, played by Michael McKell.

When DS Rosie McManus, played by Lindsey, tries to stick up for her, the strong-willed and independent Eva doesn't take too kindly to her getting involved. But the team have something more pressing to deal with - the bizarre murder of a man on a street in front of lots of witnesses.

Her problems with her colleagues aside, Eva comes in all guns blazing to this new series - which is pacier and much more engrossing than the disappointing first. On her first day she finds herself beating up an uncooperative gangster.

''I beat the hell out of him didn't I?'' she grins. ''It was camera trickery really, but we were trained with these batons that were called asps. I was quite good but then I'd had practice from before with The Bill.

''Ricky Grover, who plays the gangster, didn't want any protection. He actually asked to be beaten up. He goes, 'Hit me as hard as you can'. I hit him and accidentally scraped his finger. He goes, 'That hurt that did'. He had the right hump.''

Now though, such physicality has come to a temporary end as Diane prepares for motherhood. She has no future jobs lined up yet, although she continues to write scripts. And as for whether we'll ever see her return to The Bill, Diane thinks it's unlikely.

''I'd never say never but it's very different there now,'' she says. ''There's still some great actors, it's still a very strong show and I enjoyed doing it.

''But I think once you leave you put a distance between yourself and the show. And also I think Eva has done it all in that show. But I never say never about anything.''

* Murder Investigation Team is on ITV1 from Monday, July 11.