Movie-hype quiz time: Is James Cameron's "Avatar" the most frantically anticipated movie of the year, the last several years, or the new millennium?

Well, Cameron has been working on his 3-D sci-fi tour de force since 1995, when he first wrote the treatment for a film about aliens, genetic engineering and deep-space war. Along the way he and his team invented a slew of new filmmaking technologies, secured a budget that exceeds $200 million and managed to get the fanatics at San Diego Comic-Con drooling over the prospect of training their eyeballs on 25 minutes of "Avatar" footage months ahead of its December 18 release.

"What people like in their fantasy is a fantasy they can invest in, characters that they can recognize, that they can feel for," the director told MTV News during the convention. "Then they want to see kick-ass action."

Several of the clips Cameron screened were indeed heavy on the action. "One of them I think is just off its t--s, off the scale," he said. "The film builds to this climatic battle and the climatic battle is simultaneously huge but very intense for a small group of characters. And it's a white-knuckler."

The "Avatar" screening went a long way toward finally giving fans some concrete, 3-D-enhanced evidence to back up the years' worth of expectation. "I think there's two kinds of hype," Cameron explained. "There's kind of viral hype, which is what we're experiencing right now in the complete absence of any imagery. So I said to the studio, 'Go to Comic-Con and we'll show 'em a chunk — a real chunk. We're not going to tease with some stupid trailer and some slides. We'll show 'em 25 minutes of the movie.' "

But the imagery-based hype won't only be confined to the 6,000 or so folks who scored seats for the Con presentation. On August 21, at IMAX theaters around the world, Cameron will show 15 minutes of "Avatar" for free. The director of "Titanic" — which, by the way, remains the highest-grossing movie of all time — knows how to build buzz. And he knows what the public wants.

Yet might Cameron be worried that giving away all this free "Avatar" awesomeness will discourage moviegoers from forking over cash in December? Hardly.

"If you're there, then you liked what you saw," he said. "So you've already answered the question, 'OK, can they do the kind of emotional reality that's been missing from CG?' And I think all those questions about 'Can they do it?' 'Will it live up?' — that's going to be set by the wayside. So now, in a way, you're free to enjoy the world and enjoy the ride. That's why I don't mind showing stuff at this stage."

MTV News was on the scene at the 2009 San Diego Comic-Con. Visit MTVNews.com, Splash Page, the MTV Movies Blog and Hollywood Crush for videos, interviews and the latest news on "New Moon," "Iron Man 2" and everything in between.

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