Were you familiar with Tolkien's work?

I hadn't read the books. I'd read "The Hobbit", which is Tolkien's introduction to "The Lord of the Rings", but I came as an outsider who scarcely knew who Gandalf, the character I am playing, was. I rapidly learned that there are millions who know who Gandalf is and are waiting breathlessly to see what the films have made of him and the other characters. So I was a late believer.

What made you decide you wanted to play Gandalf?

What convinced me was not my knowledge of "The Lord of the Rings", which didn't exist, but Peter Jackson and [Jackson's wife and co-writer] Fran Walsh's enthusiasm. They came to my house in London and showed me some of the initial sketches for the design, which were terribly impressive. They were already half way through the journey, but to be asked to join them on this expedition - akin to climbing Everest cinematically - I knew it would be something I'd regret if I didn't do it.

Do you think it is more than just a fantasy film?

The story is too important - the issues Tolkien so imaginatively dealt with are central to human life and brilliantly achieved in the book, and now in the film. So yes, I feel it's probably more than just a fantasy film.

Was it a tough shoot?

There were long days. A lot of the make-up and costumes were cumbersome, and there was arduous terrain to be clambered over. But it's not real hard work. If you see in this film Gandalf leaping onto a horse without a saddle or a bridle, it's not me. It's not this actor!

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