Playing Sgt, Trotter in 'The Mousetrap' is the same as playing Scripps in 'The History Boys,' in the sense that they're dream roles that I've always wanted to do. The fact they're letting me do this professionally and I'm getting paid for it, I find astonishing.

I've always got into stunts; even at drama school, I was falling down trap doors, and swinging in on ropes.

You know the stories of a woman saying to Churchill, 'Sir, you're drunk,' and he said to her, 'And you're ugly, but in the morning I'll be sober.' I was really excited to do that scene, but I did get slapped.

I was sad to leave 'Downton,' but I will always remember it fondly, as they did me a lot of favours. I owe them a lot.

Playing Sgt, Trotter in 'The Mousetrap' is the same as playing Scripps in 'The History Boys,' in the sense that they're dream roles that I've always wanted to do. The fact they're letting me do this professionally and I'm getting paid for it, I find astonishing.

I really love a challenge, but in 'Downton' it was really hard going because there's no CGI - what you see is what you get. These were real explosions right in front of our faces, and you just had to make sure that you cleared out of the way.

There are a lot of dream roles that I couldn't do, like James Bond and Indiana Jones; I'd never get a look in there, but actually, Doctor Who is probably the only one that I could because he's quite quirky, and the fact that he regenerates he can actually be anyone. So one day, who knows, I might have a chance. I'd love to play that part.