James Cameron has revealed that the 'Avatar' franchise came to him in a teenage dream.

The 68-year-old filmmaker has helmed 'Avatar: The Way of Water', the long-awaited sequel to the 2009 sci-fi epic, and explained that he first thought of the idea as a 19-year-old college student.

James did some drawings that became very early concepts for the franchise but would have to wait a long time to get the project on the big screen.

In a feature for GQ magazine, the 'Titanic' director said: "I woke up after dreaming of this kind of bioluminescent forest with these trees that look kind of like fibre-optic lamps and this river that was glowing bioluminescent particles and kind of purple moss on the ground that lit up when you walked on it.

"And these kinds of lizards that didn't look like much until they took off. And then they turned into these rotating fans, kind of like living Frisbees, and they come down and land on something."

James explained that the drawings "saved us from 10 lawsuits" as nobody else could claim that they had thought of the idea.

He said: "It was all in the dream. I woke up super excited and I actually drew it. So I actually have a drawing. It saved us from about 10 lawsuits. Any successful film, there's always some freak with tinfoil under the wig that thinks you've beamed the idea out of their head. And it turned out were 10 or 11 of them.

"And so I pointed at this drawing I did when I was 19, when I was going to Fullerton Junior College, and said, 'See this? See these growing trees? See this growing lizard that spins around, that's orange? See the purple moss?' And everybody went away."