When you start playing a character every day for seven weeks, it suddenly starts becoming easier.

When I went to the Oscars - the only time I've ever been to the Oscars - a few years ago, I wore this Prada dress covered in cooking utensils. I got drunk at the end of the night and started ripping them off and giving them as presents to people, so that was fun. I'm pretty sure that was the point of it, that's how Miuccia meant for it to go I'm sure.

It's actually easier to play a leading role than it is to play a supporting role.

I've never been obsessed with celebrity or star-struck or anything. I met Penelope Cruz when we were in Toronto, who I think is a goddess and an unbelievable actress, and she introduced herself. As she walked away from the table I had to take a deep breath, which was strange because I've never had that with anyone.

I remember in 'Pride and Prejudice' I had to do a scene where I broke down. And before we filmed I spent like three hours imagining my mum's funeral. Actually, she's very much alive, happy and healthy. It was really horrible.

I was trying to find ways of not being pigeon-holed like that. I didn't want to be tied down by my accent. I wanted to play Americans. I don't want to ever be doing the same thing twice, and I just didn't want to repeat myself.

I probably dreamt about running off to America or something when I was 16 because it just seemed like I was studying algebra and going, 'What am I going to use this for?