I had the best teacher in the business. Kevin Costner was my teacher. I was acting opposite him and he was directing me. The way he directed me, for which I am eternally grateful, is he would watch the scene back on the monitor, which is sort of considered unfashionable - you're not meant to watch yourself. But he was like, "Come around. Watch this. See there, you're doing a great reaction, but you're doing it out of frame." That was exactly what I needed. I learned how to act on film from him.

My husband Rhashan reminds me of my father because he's got great strength of character.

Ewan McGregor is a very genial and entertaining man, and Pierce Brosnan is possibly the nicest man in the world. Actually, it was quite a genial set The Ghost Writer, but the weather and the colors and the actual surroundings were oppressive. But it was a created atmosphere. What was so striking is that Roman Polanski had his crew from The Pianist, and we were shooting in Berlin, so there were German and Polish and French people, and I was just sort of enjoying being in this mix of people, all kind of rubbing along together. That felt good.

My agents were like "Come to L.A., we've got meetings for you." I was like "No, I'm doing this now." Then my father became very ill back in England, and I didn't want to be away. I went back to England and did a bunch of crazy indie movies, all of which I loved with a passion, and none of which did any business.

I don't tend to spend the whole day in the personality of the person I'm playing.

I was lucky, because Ewan McGregor had already been shooting with Roman Polanski for about a month before I got role. And he did a faultless impersonation of what it was going to be like. So when direction happened, it was like, "Oh yeah. That's what Ewan said was going to happen." And so it was a little bit less debilitating than it might have been.

I hope I never get in the situation where I refuse to audition, because I think people have a right to see you interpreting the character, and if you don't do it the way they want you to, they have a right to say, "No."