Your character, Hester, has been significantly boosted from her subsidiary role in the novel...
In the film she is very much one of the front runners. She's a true heroine of the story as well because she gets very much involved in the code breaking along with Tom Jericho, played by Dougray Scott. And she is good. At Bletchley Park Hester is employed below her level of intelligence. In the book she never actually gets to break any codes herself. However, throughout the story of the film she gets a lot more involved.

Were you good at mathematics at school?
Actually I was. I was addicted to it. I don't know why.

Do you think that the period in which "Enigma" takes place, the 1940s, were better times aside from the war?
I think society was a lot nicer back then. Society towards women and how women look or should look now is completely screwed up. The great advantage now though is that women are allowed to have big boobs. All women want big boobs, so it's like, finally they are realising that we're supposed to have boobs. But beneath the large boobs we're supposed to have stick thin bodies. That drives me crazy. 1940s fashion was so attractive for women. The clothes and the hair styles were all absolutely gorgeous.

What film do you hope to do next?
It's called "Therese Raquin" after the novel by Emile Zola. It's a wonderful, kind of bizarre crime of passion story. The director David Leveaux did theatre previously. It'll be shot in Britain.

"Enigma" is released in UK cinemas on Friday 28th September