Interestingly, this character [Doctor Nash] is probably closer to me than somebody like the evil Sir Godfrey in Robin Hood or Lord Blackwood who wants to take over the world in Sherlock Holmes. This is a character that's English, he's based in London, and so it's closer to me than a lot of stuff I've been doing recently.

The Secret Service I'm really excited about because Matthew Vaughn directed it. I've done a couple of movies with him - Stardust, which is one of my favorite films, and Kick-Ass, which is just a crazy, wonderful movie.

I had this extraordinarily bizarre moment when, two Fridays ago, my missus gave birth to our second child at 11am and by the same time the following day I was sitting around a table with Ridley Scott, Russell Crowe and Leonardo DiCaprio in Rabat in Morocco, rehearsing a scene we were going to shoot the next day.

I loved making The Imitation Game and it's really gratifying to hear the audience's response to the character that I play. It was just a little thing that I did because I really liked the film and I liked Benedict [Cumberbatch] and I loved Morten's [director Morten Tyldum] previous film, Headhunters. For me, it was something I did thinking, "Wow, this is a lovely quality piece of work."

The idea of transformation - playing something I'm not - is the bit I enjoy most about acting.

I just like voicing films in general. I do a lot of documentary work and it's a short hop really to narrating a character, especially if you're on film and you're there in a visual way. It sounds obvious, but voicing an animation really focuses you on the way that you're communicating through your voice. It's a very specific ability that you need to be able to have in order to pitch it just right.

The important bit for an actor is the actual shooting of it, because the minute the shoot ends, it's got nothing to do with you anymore.