The idea is that Jodie Foster is with her child and she's going back to New York from Germany with her husband's body. She loses her child on a plane, and you think, 'How can that happen?' There's no record of her having brought a child onto the plane, and the captain is left wondering about whether she's telling the truth. You never really know if she's telling the truth or not.

I sometimes find that playing the bad guy, or villains, or psychopaths tend to be much more psychologically rewarding. And you can really push it, you can push the limits, and get away with it.

The idea is that Jodie Foster is with her child and she's going back to New York from Germany with her husband's body. She loses her child on a plane, and you think, 'How can that happen?' There's no record of her having brought a child onto the plane, and the captain is left wondering about whether she's telling the truth. You never really know if she's telling the truth or not.

I think everybody's got different methods of working which suit the particular individual. Mine is to sort of play the part, and give 100%, to concentrate and focus on it while I'm actually working, but then leave it behind until the next day.

Lord of the Rings was something I always wanted to do. I read the book when I was about 25, and I was always hoping if it was ever made into a feature film that I would be involved in some way. And then I finally got it, and I was over the moon. It was fantastic news.

I think that you always have something left, that you take something of the character with you.

I'd been trying for a while to get parts that weren't just the English bad guy, so it was quite refreshing to be playing someone who was a compassionate, decent guy.