Cool to see you guys are interested. There's a good interview with the director on the Guardian site here. If you want zero spoilers don't read, although what is given away isn't a huge deal with the book or I guess the film, as it's up there on IMDB. The set up's preposterous when you hear it but it's the journey thats cool, at least that's how I found the book.
Dude took ten years to figure out how to turn the book into the film. Madness.