I've always been quite an active person especially when I was younger. When I was in primary school, I used to play lots of sports. I was a sprinter and I did basketball and swimming and Gaelic football and things like that. So I always thought, I guess, that it would be fun to incorporate that much physical activity and work into a dramatic piece.

I was 12 and I remember every­thing. I mean, I had done two films before that. The first was actually with Amy Heckerling. It was so brilliant to work with her on my first film. Atonement was the third one I'd done, and I remember how it felt to arrive on set every day. I remember how it felt to get my wig off at the end of the day. I remember how hot it was.

Joe Wright was almost like a teacher, to be firm with me, that really stuck with me. And that helped me as I've gotten older.

There's no one out there like Quentin Tarantino. His films have a signature look, and they never just stick to the same kind of story.

If you don't have eyebrows, you don't really have a face.

When I was younger, I would mess about and have a laugh with everyone. I was doing Atonement when I was about 12, and as we went to do this very serious scene, the director Joe [Wright] came up to me ... I'd been giggling right up to the beginning of the take. And he came up to me and said, "Okay, you need to be serious now." I completely idolized him.

Once you move away from home, it's never quite the same again. You expect everything to be just as you left it, and it never is. It's almost the first step into adulthood, realising you've got to make your own way.