"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."