The cast of Avatar: The Way of Water revealed how worried they were for James Cameron's life due to his ocean obsession.

In an interview with The New York Times to promote the upcoming Avatar sequel, Sigourney Weaver discussed her fears for Cameron following his expedition to the bottom of the Mariana Trench. "We kept thinking, 'I hope he survives to make a new movie,'" Weaver said. In March 2012, Cameron traveled seven miles below the water's surface to reach the Mariana Trench, the deepest location on Earth. The Titanic director became the first person to complete the underwater valley adventure solo.

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Avatar: The Way of Water will feature many underwater scenes in the universe of Pandora. To achieve the scenes, Cameron had "the world's best breath-hold specialists" to teach the cast how to improve their breath-holding times while submerged in large water tanks, instead of using CGI. When asked the reason for using actual water, not special effects, Cameron replied that it simply "looks good."

"Come on! You want it to look like the people are underwater, so they need to be underwater," Cameron said. "It's not some gigantic leap -- if you were making a western, you'd be out learning how to ride a horse. I knew Sam was a surfer, but Sigourney and Zoe and the others weren't particularly ocean-oriented folks." However, in another interview, Cameron claimed the Avatar sequel's water is "mostly CG," but audience members wouldn't be able to tell the difference.

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Avatar: The Way of Water Opens in December

Released 13 years after the original Avatar, the upcoming sequel fast-forwards the plotline 15 years with Jake Sully and Neytiri as parents. Weaver plays one of their five children, Kiri, a 14-year-old Na'vi. Despite how commercially successful the 2009 film was, Cameron had his doubts about how well Way of Water would perform. "I was a little concerned that I had stretched the tether too far, in our fast-paced, modern world, with Avatar 2 coming in 12 years later," Cameron said.

In addition to Avatar, Cameron has also explored his fascination with the ocean for Titanic. In total, the director spent more hours on the sunken ship than Captain Smith, the captain of the RMS Titanic, himself. Seated around 2 miles under the ocean off the coast of Newfoundland, Canada, Cameron has traveled 33 times to the ship's wreckage.

Avatar: The Way of Water opens in theaters on Dec. 16.

Source: The New York Times