There's something scary about acting always, because basically you do all this work in a vacuum, and then suddenly there's a lot of money spent making a film, and there's suddenly a camera here, going, 'Right? What are you gonna do?'

It can be a miserable profession, acting, because you always want what you can't have.

I find in film acting that however many years you have done it for, you can feel totally relaxed and at ease with the people around you, absolutely wonderful, then roll camera and a little part of you goes, 'Ugh'. It is learning how to manage that.

A lot of people think theatre must be much harder work than film, but anything histrionic or superfluous gets seen on camera so you have to work to distil it into a complete sense of what's true.

My first film, 'Like Minds,' was with Toni Colette, who was extraordinary. I mean it was basically a mini-masterclass for acting on film at a time when all you could probably see were my eyebrows bouncing up and down on screen.

When you're doing a film that has so many effects, you do a lot of it on green screen, and you can't see what that world is.