I never sit in a cinema and go, "Ah! I want to be in that film!"

It makes it easier, if you can't do an American accent. I don't know. It's different. I played a character in Never Let Me Go where the script for my character was very sparse, and I enjoyed it. With Never Let Me Go, I had a whole book written from my character's point of view, so I always knew where I was. But, with Ryan [Gosling], it was just easy. He's such a brilliant actor and he is so prepared. He doesn't have to warm himself up to be in a scene. He's just in it. It draws you in, in a way.

With theatre especially, you don't want to do it unless you love it - there's no way you can pull it off, making people happy, making yourself happy for 12 weeks or whatever.

When you do bigger jobs there's more attention and when you film in New York you get loads of paparazzi everywhere. It affects your work because you're trying to think about the person you're acting with and you've got 20 other lenses taking pictures of you at the same time, and it throws you.

In London, people can be so... well, it's not even a case of people being unkind or unfriendly. You just don't make any contact in London. You go from A to B with your eyes on the pavement.

My agent in London told me, after Never Let Me Go, because I loved doing that so much, "If you're on a lucky streak and you're doing well, you should only take a part, if you can't bear the idea of anyone else doing it." That's been the case since then, with Drive and Shame and the play (The Seagull), and the stuff that's going on, like Gatsby. I would have been devastated, if I hadn't gotten those jobs.

Posing on the red carpet feels like you're selling something that has nothing to do with you. If you do it with someone else, it's like we're saying, 'Oh! We come as a pair! Would you like to buy both of us? We're available for weddings and Bar Mitzvahs!'