The fifth series of Law & Order: UK begins this weekend on ITV1, with former Doctor Who star Peter Davison joining the cast as “down to earth pragmatist” Henry Sharpe, who takes over the job of Director of the CPS.

> Buy the Series 1-4 boxset on Amazon.

Series 5 Episode 1 airs at 9pm on Sunday 10th July on ITV1.

You’re currently playing two lawmen; Professor Callahan on stage in the Legally Blonde musical and Henry Sharpe, new director of the Crown Prosecution Service in Law & Order: UK. How do they compare?

“They don’t really compare at all; there is a stark contrast between Callahan in Legally Blonde, who is very successful but rather arrogant and enjoys the power trip of lording it over his students, and Henry Sharpe who is driven by the pursuit of justice.

“My career seems to go in phases. I’ve gone through the doctor phase, the policeman phase and I’m now in the lawyer phase! If I had to follow one of these professions I would probably be a barrister as it is the closest thing to being an actor – the theatricality of it; all that performing in court.

“Being a barrister seems a bit like being in Parliament; opposing sides shouting at each other in court, or in the House, then propping up the bar together afterwards, leaving animosity behind. And there is something endlessly fascinating about the juggling of law versus justice to get a result.”

Playing the director of the CPS in Law & Order: UK, you must be is very aware of the importance of the end result…

“Getting a result is an issue that keeps affecting my character. And sometimes it is about compromising. Sometimes he knows they’re not prosecuting the defendant for the right crime but they might have to be content with that because he can’t risk wasting the tax payer’s money. So if it means getting a conviction for manslaughter as opposed to losing a trial for murder then so be it. He needs the guilty verdict. Consequently they can only prosecute when confident about the result.

“Ultimately Henry wants justice out of the process. He is driven by the pursuit of truth and justice to work in the CPS because it’s not about money. If you’re good you have to be very dedicated because if you had your own firm the money would drive your ambition.”

Can you tell us a bit more about your character, Henry Sharpe…

“I think Henry is a good boss. He is very inclusive and listens to what his team say to him. He is not aggressive but if he has to he’ll tell them off and put them on the right track. There is no dark side to him. He is in a position of power and trust for a good reason.

“I think he’s an amiable man. He has made a career of this and thinks he is doing a good job. He can be tough when it is needed and he has to be pretty tough to be in that position. What troubles him is this feeling that he can’t waste money – it’s that Daily Mail headline he lives in fear of. He has to think about public reaction and opinion.

“The reality of the situation is it’s a game of cat and mouse. The defence barristers will do anything to get their clients off, so occasionally Henry and his team have to bend the rules a bit to even the playing field. They may bend the rules to get justice and that is what has always fascinated me; the difference between law and justice, because they are really not the same thing at all. The law can get someone off quite easily meaning justice isn’t served.”

Are you a fan of the Law & Order franchise?

“What’s so great about Law & Order: UK, is that for us it is almost completely about the case that develops from the crime to the courtroom. We don’t waste time on the other stuff. I had to stop watching the show when I got the part as I saw my character’s predecessor, George Castle, on screen and started worrying as I had to step into Bill Paterson’s shoes!

“I think it is a good series with empathetic characters. From the point of view of a leading character you want to feel what the audience feels. For the most part I play fairly nice people.

“Dangerous Davies, my character in the Last Detective, was doing the best he could but Henry has more on his shoulders. I try to make him a bit more human. I imagine him a bit like my uncle John who worked in the city. At home you would never believe he was a city high flyer because he was an amiable and happy family man. I like to think of Henry as having a house full of teenage children and a rather eccentric wife!”

What’s it been like working with your new team?

“It has been fun working with Freema and Dominic and they are both excellent actors. Freema’s character, more than anyone, gets to the heart of the cases. Her position is to raise the questions and nudge us in the ribs. I met her while she was still doing Doctor Who, my children were very taken with her – we are big fans of the show. She helped me out with a video for a Doctor Who convention.

“Doctor Who is a prestigious programme now, a front runner for the BBC. I’m very happy for Matt Smith to have usurped me as the youngest ever Doctor – they all seem to be getting younger and younger.”

And your own daughter Georgia has recently had a daughter with her fiancée, former Doctor Who star David Tennant…

“Being a granddad again is great. This is my first grandchild who will be separated in age from her cousins [Peter’s two sons are around the same age as Georgia’s son]. I love little babies so it is nice to go round and be a grandpa. It is a fun role and one I enjoy.”

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