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.

You need to try to find a way to humanize your villains. Genuine villains, in real life, still have mothers and daughters and sisters, and they fall in love. They don't walk around with a big sign saying, "Bad guy," on their head. They think they're good guys. If you can play that, I think it makes it more interesting.

In the movie, you have to decide as an actor how you are going to give a character presence. You can't really move, walk, and talk like yourself. This creates something so you have to find something "other".

I think it serves the purpose of the film if the premise is that you're unsure of me because you've only ever really seen me play villains.

And I think in your 40s, you land a little bit, physically and mentally, you arrive at a place where you feel you've learned some stuff. Having children at that point meant I had something very useful to do for the next 20 years.

In the film industry you never really know if all the various ingredients will come together - sometimes they do, and sometimes they don't. As an actor, you don't have much control over those things. It's a director's medium in that sense. All you can really do is minimise the risks of being involved in something that might not work and look for something that also suits you.

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