I'm a mixture of Anglo-Saxon, a bit of Spanish and one-eighth American. I've often wondered if I have an Asiatic ancestor from the East as well because I have deep-set eyes. Make-up artists are constantly trying to shade my eyelids, and I have to point out that I don't have any!

Carey Mulligan is completely self-possessed. She knows what she's doing, and again, quite like the big-hitters I was talking about, my job was just to feel and reflect back the amazing performance coming my way. If anything, I was slightly pathetically flying in her tailwind. She's an extraordinary actress.

Usually the casting process is lengthy and humiliating, but in this instance, The Ghost Writer, it was just too easy. I was sitting in a rental car on an L.A. street and my cell phone rang, and it was Roman Polanski on the line. I couldn't really believe my luck. He said, "See you in Berlin." I sat staring at a palm tree, thinking how surreal that was.

If the role is right and it's another situation of having a benevolent genius at the head of it, someone who likes actors, and will protect the actors from the ravages of reality-TV drama. It's a brutal world, and you need to have a strong creative team who can stand up to the network.

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

When The Sixth Sense was the No. 1 movie in America, I had a Canadian boyfriend whose only assets at the time were a guitar and a van. I don't know what I was thinking.

I am the worst judge of how a movie is going to do. I always have great and ambitious hopes, but none of them see the light of day.