'Avatar' Director James Cameron And Cast Talk In MTV News Chat

'If the movie makes money, then all things are possible,' director says of sequel chances.

Why are the aliens blue? What's the most butt-kicking weapon of all? Is this just the beginning of an enduring sci-fi franchise? All these questions and many more were answered by James Cameron and the cast of his 3-D alien escapade [movie id="301495"]"Avatar"[/movie] during MTV News' live-stream chat on Thursday.

The 30-minute conversation began, though, with talk of the mammoth expectations surrounding the film — Cameron's first feature since 1997's $1.8 billion-grossing "Titanic."

"I knew that would be the case," the director said. "It makes you a better filmmaker when you know you've got a lot of fans to please."

Sam Worthington — former Marine Jake Sully in the film, who travels to the world of Pandora to explore the territory via a mind-controlled blue avatar — said he paid no attention to all the hype. "None whatsoever," he maintained. "We stand by our project, stand by the movie we made."

And it certainly took awhile to make. Cameron started the brainstorming process in the mid-'90s and the filming and effects-work process stretched on for years. "I thought it was for James Cameron's private videos," Worthington joked. "I didn't think it was coming out."

Added co-star Zoe Saldana, "We came back [to the set] doing cartwheels!"

Fans also got to ask their own questions, and one viewer wanted to know why Cameron chose to make the aliens blue. The director explained that he wanted there to be an "otherness" to the love story between Sully's avatar and the native alien, played by Saldana. Since skin color is, as Cameron said, "such a big issue on our planet," he decided to use that issue as a thematic driving point. Many skin tones in the possible color palette were already taken by humans, while green had been employed by just about every alien movie ever made.

"We had big blue women, not little green men," Cameron said.

Worthington said his response to questions about this interspecies love story is simple: "Come on, man, grow up! It's her spunk and her spirit that he falls in love with. Look beyond how you look."

But "Avatar" is not just a love story — it's also a kick-ass action flick. Cameron revealed that one of his favorite weapons is the amp-suit cannon, a device that can inflict some serious damage to the Pandoran environment or anyone unlucky enough to step into its path.

While the film doesn't arrive in theaters until December 18, fans are already talking about further installments in what many are hoping will become an enduring sci-fi franchise. If all goes according to plan, Cameron made clear, an enduring sci-fi franchise we shall get.

"If the movie makes money, then all things are possible," Cameron said. "And if it doesn't, we'll just pretend it didn't happen."

Cameron has more stories to tell and visions of further video game titles following on the one published by Ubisoft. So do Worthington or Saldana know what the director has in store?

"He's given us little tidbits," Worthington admitted, but nothing more. "He's James Cameron. You don't f--- around with him!"

Check out everything we've got on "Avatar."

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