Olivia Colman interview Broadchurch

Olivia Colman is the TV actress of the moment. She can play comedy, tragedy and wins over an audience immediately. Her turn in the comedy Twenty Twelve, with Hugh Bonneville, was a highlight to the series. After film roles in Iron Lady, Hot Fuzz and Hyde Park on Hudson, the Cambridge graduate, who met Mitchell& Webb at college, is now one of a clutch of new TV detectives.

The drama appealed immediately, says Colman. “I really liked the idea of the story, a hard story and an upsetting one, but also the idea of a whole community being affected by something and I warmed to the character of Ellie [her detective character]. Then I heard David Tennant is going to do it and Vicky McClure and all these extraordinary people who you think are wonderful.

The actress had sympathy with Ellie, too.

“I find it hard to play a character if I can't feel any of me in them. Especially if you are going to be playing that person through the whole series you need to feel that connection.”

She adds: “I see Ellie as a jolly good egg and in it for all the right reasons. It feels like the best way to serve her community is to be part of the police. She is from Broadchurch, knows everybody, loves her community and then is probably out of her depth when this terrible thing happens. But thankfully Hardy [Tennant] joins the team and, although they're not keen on each other she learns from him.

“There is definitely a personality clash between the two. She doesn't like him because he's taken the DI job she was promised. That's a stumbling block Ellie finds hard to get over. But as the case goes on she realises he really knows what he is doing even though his methods are socially difficult for Ellie to watch. I think they have a grudging respect.”

The sense of community in Broadchurch is familiar to Olivia. “I grew up in north Norfolk,” explains,” Colman, 39, “which certainly used to have an enormous sense of community. There are more and more second homes there now so I’m not sure how that has damaged it. But where I live in South London there is a beautiful community; it’s the friendliest place I have ever lived which comes as a surprise to non-Londoners. Once you find your community it is awesome. I know all the parents at the school gate, all our neighbours, everyone in the local shops. I love it there.” Olivia had to adopt a West Country accent for the role of the Dorset detective. “It's only a very mild accent anyway. I didn't want people to spend their time going, ‘What the hell accent is she trying to do?’, I just wanted it to be unobtrusive really.”

Unlike the west country weather, she says, which was a surprise.

“It turns out I really don't like being cold! I had a bit of a sense of humour failure one particular day when I thought, ‘I don't want to be outside anymore’. There was horizontal rain going into our eyes and it was freezing. Dorset is quite a rainy county but being on the cliff at Bridport in the sunshine during the first week of filming was just amazing. Idyllic. Then we went back in the winter and the sea was really dark and angry grey, it was freezing cold doing night shoots and that's when I started to wish I had a different job!”

With the murder of a child at the centre of the story, Colman found some scenes distressing. “I found it really hard doing the emotional scenes with Jodie Whittaker and Andrew Buchan, who play the parents of the dead boy, talking about their tragedy just because they are such beautiful actors and I had a hard time keeping it together. My character wasn't supposed to cry half as much as she ended up doing but I couldn't stop myself; it was so sad.”

She was also kept in the dark over the question vexing the audience: who did it?

“This was my first time playing a plain-clothed detective and we had no idea who committed the murder. I hadn't worked like that before. Normally you do have a whole set of scripts before you start. But it was quite exciting, everyone looking at each other wondering who is the killer, which is sort of what you would feel being in that community. We were all taking punts on who we thought it was as the whole cast and crew were in the dark!”