I kept expecting any moment that he was going to say "OK we've heard enough from you now, let's go and make our movie". But that never happened 
Novelist Louis Sachar has written over 20 children's books. First published in 2000, Holes became an overnight bestseller in America, winning numerous awards and becoming part of the school curriculum all over the country. He had a hands-on involvement in the film adaptation, penning the screenplay.
One hears all the time about the sorry way writers are treated in Hollywood. Were you nervous?
I was very worried about that. I just sort of figured, well, you sell the rights and hopefully something good will be done with it. But I didn't really have any high expectations. I talked to Andy [Andrew Davis, the director]. I admired his work - I loved The Fugitive - but I was very worried going into it and I was surprised when he asked me to write the screenplay. And then he just kept me involved every step of the way. I kept expecting any moment that he was going to say, "OK we've heard enough from you now, let's go and make our movie." But that never happened.
How difficult was it to find the right actor to play Stanley Yelnats?
The character in the book is overweight. So I was concerned when I was told that Shia [LaBeouf] would be cast, not because I thought he had to be overweight - I didn't think that was an essential element of the story, it was mainly that he felt like an outsider and was vulnerable - but because the book had become such a success I thought people would come to the cinema, see Shia, and think "That's not Stanley". But that hasn't been the case. Shia conveys the right emotion, vulnerability, and the right kind of quirkiness. I've never heard of anyone complaining that he's not overweight.
Did any of the adult actors surprise you in the ways they approached their roles?
Sigourney [Weaver] was very much like the way I'd always imagined her. And the take she took on the character was just right. I think she could have gotten it very wrong and turned her into Cruella de Vil or something, but she didn't do that. She made her somewhat pathetic, so that you feel sorry for her. I've always felt sorry for The Warden and Sigourney captured that. Jon Voight transformed Mr Sir, and in a good way I think. He certainly created a difference between the Mr Sir of the screen and the Mr Sir on the page.
What was your emotion on seeing the finished film?
It was so much better than I imagined. When I was on the set people kept telling me that there's three movies: the one you write, the one they film, and the one they edit. That is really true. A lot of the things I watched getting filmed I thought weren't working, but when I saw the finished film they were wonderful.
Holes is released in UK cinemas on Friday 24th October 2003.
