What is so beautiful about these books is the dance of the darkness and humour. That is what we were trying to honour 
The Prisoner Of Azkaban, the third and best picture in the Harry Potter series, is directed by 42-year-old Mexican Alfonso Cuar贸n. Along with Alejandro Gonz谩lez I帽谩rritu and Guillermo Del Toro, he is at the front of a new wave of hip Mexican filmmaking talent crossing the border into Hollywood. His arresting visual style and track record with young actors made him a popular choice to take on JK Rowling's world of wizardry.
You're the new boy in all this. Your producer David Heyman called you a teenager at heart. Is that why you were picked to direct this film?
Well, teenagers recognise other teenagers. From the moment I read the material, it was something that I connected with. This is the story of a kid who is seeking his identity as a teenager and I felt it was something I knew how to make into a film.
Were you surprised to be asked?
I was amused about the whole thing. I was amused because it would have made perfect sense if I'd been asked after a little film I did called The Little Princess, but it came right after I did Y Tu Mam谩 Tambi茅n.
How was did the three principals react to you as the new director?
Something happened with the three of them that I think also happened with the rest of the actors. Because of my bad English, they would do what they thought I'd said, not what I had actually said [laughs]. And that was to the benefit of the film.
Were the kids intimidated by working with the likes of Gary Oldman?
From my perspective, I found the grown-ups more intimidated by the kids. They'd done two movies, they are doing this movie, they are working every single day. Then Gary comes in from a different universe. I think it was tough for him.
Could you comment on the choice of Michael Seresin as cinematographer? Most of his films have this gritty look, particularly his Alan Parker films, and this one looks dark - even darker than the first two films...
All my life I collaborated with Emmanuel Lubezki - he did my films, and also films like Sleepy Hollow - but he wasn't available. For the first time ever I found myself looking for a different cinematographer, and actually Emmanuel was a big factor in choosing Michael Seresin. We talked about him as a cinematographer we always admired, and one who we tried to emulate in many ways. One thing that I felt was perfect for Michael was that we have this magical universe that he could really ground. Because he has got that grittiness, and that grittiness comes from the fact that he is a single-source light cinematographer. He's very naturalistic in that sense. I felt it would be a good marriage with the material. He also turned out to be an amazing guy and an amazing collaborator, and I think that the combination between Michael Seresin and Stuart Craig [production designer] is what put this universe together.
Did you ever feel the need to reign in some of the darkness, or were you told that you could push it a bit further?
From the get-go we set up to serve the material, and I think that the darkness comes out of the material. There is an evolution between the first film and the second film that is also a result of the material, and now this new darkness has come up from Harry's perception in which the world is changing. Some of the monsters are not outside, the monsters are inside, but also the antidote for the monsters is inside. So we were trying to add darkness, to balance the darkness present in the book. What is so beautiful about these books is the dance of the darkness - the scary, emotional elements - and humour. That is what we were trying to honour.
As a Mexican, how did you give such a British atmosphere to the film?
The Britishness was kind of easy because it was so obvious in the material, so strong in the material. The thing that made it even easier was that I inherited a universe, not in the books, but it was already set into films. I was inheriting what Chris [Columbus] put together in the first two films. When I started I had it easy, everything was already in place. I just came here to have fun. You have to talk to Chris, because he had to build the kitchen, buy the food, get the recipes and start cooking. I arrived and the kitchen was there, the food was there, the recipes were there and not only that, the chef was there from the previous two meals telling you "watch out for the oven because at 350 it's not working so well". The only thing that I did myself was to serve the material, but I was serving it from a very comfortable standpoint.
