RB: So much of the previous writing work you've done is not based on preexisting material. Was it hard for you to work from that?
MNS: What really made me feel okay about it was that I wrote Stuart Little, and I so enjoyed that. In Stuart Little, there was a line where one of the characters says in E.B. White's book, "My, he looks somewhat like a mouse." I understood the movie right then, and I was like: "Okay, I got it. This is a world where it's strange that their child looks like a mouse, but it's not totally unusual." I was like, "That's how everyone's going to talk." Then I said: "What's the movie about? It's about family." I made it my own, and I felt really excited and rewarded by that process. So I was hoping it would be that way on this one, and it really has turned out that way.
RB: In its summer movie preview, Entertainment Weekly credits you with having a "a supernatural knack for casting kids." How do you coax such real and affecting performances out of young actors?
MNS: It's really simple. I don't look for Daniel Day-Lewis at 12 years old. That's not what I'm doing. I'm looking for a perfect human being to cast. One that matches my character and someone that I like. I can't tell you how many actors and actresses I have met with who are incredibly talented—now I'm talking about adults—but when I sit down with them, the energy they're giving off of who they are, I walk away and I think, "I can't do it with them because, ultimately, I'm going to keep peeling away and peeling away and there won't be the person that I want there." So no matter how good their acting chops are, it's going to be a futile exercise. But this is reverse. There's no acting chops with these kids. Basically it's just letting their essence come out, their humanity. With Noah [Ringer, who plays Aang] I thought his personality and who he was as a human being was so unique. He's home-schooled, he didn't really watch TV at all in his whole life—I don't even think they had a TV—he was an unusual individual. He would be timeless, and he's such a good kid. And he's a martial arts expert. I just promised, we will talk about Aang until Noah understands him, and we will respect Aang. I talk to the kids as if the fictional character we're trying to create is real. We respect that person until he comes to life. And I never talk down to kids. Never ever talk down to them.