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

For me, selfishly, The Postman didn't kill my career. It meant I didn't shoot straight and painfully into the limelight, but Rushmore came out of it. No one would have known where I was to cast me in Rushmore had I not been in The Postman. Because they shared a producer. Nor would I have been in The Sixth Sense. Nor would I be speaking to you now if Kevin Costner hadn't cast me in The Postman.

Joss Whedon writes beautiful drama. His sensitivity and his sense of drama and scenes are pretty exceptional. There's no one else writing like him, really, in sci-fi and TV. That's not to say there are no astonishing writers on TV. I was nervous about coming to America and playing an English person who speaks very English when all the writers are American, because it's a very particular thing to imitate, and if it's badly imitated, it sounds painfully contorted and silly. And he writes very well for English people. It was Joss Whedon who persuaded me.

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.

There are movies where I've walked onto the set and felt, "This is home," and I'm confident in myself and my work, but that was my first experience of live TV. At that stage, Friends was at its unassailable height of popularity and brilliance.

From a very young age, I wanted to get up on stage whenever I went to the theatre - the actors just seemed to be having so much fun. One of my worries about theatre, in fact, is that the actors are quite often having more fun than the audience.

Family holidays and weekends are really brightly colored memories, full of my mother and father, rather than our nannies and au pairs.