James Cameron's upcoming sci-fi sequel Avatar 2 will feature groundbreaking underwater technology, and the long-anticipated sequel is far from director James Cameron's first time exploring the deep blue. So why is the director so obsessed with pushing the boundaries of what is possible underwater, not only in film-making but beyond it into the scientific world?

As the sequel to the highest-grossing original film of all time, Avatar 2 already has plenty going for it. It also has an incredible weight of expectation behind it, with Disney no doubt hoping for an opportunity to rival Star Wars' box office draw with another major franchise. Even with significant marketing weight behind it and a huge established audience, Cameron continues to push the envelope, with hype building around the film's extensive underwater sequences. The Avatar franchise obviously relies on a lot of motion-capture technology, so filming underwater only further complicates that process, but the new techniques will change how motion capture is achieved. Of course, with reports that actress Kate Winslet has set the record for longest underwater sequence, it seems Cameron has accomplished yet another improbable underwater task.

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The ocean has been a frequent presence throughout Cameron's filmography, confirming the 66-year-old's fascination with it. The director got his start in 1982 with Piranha II: The Spawning, a much-maligned debut that his since developed into a cult classic. Of course, the extent of Cameron's exact involvement with the film remains unclear but it set a path all the same. And by the end of the decade, Cameron managed to deliver a true underwater classic in the form of The Abyss, a film that remains just as beloved as it is controversial for its grueling, underwater production. Tales from the set of The Abyss suggest Cameron's dictatorial directing style, but also highlight his commitment to revolutionizing underwater filmmaking. That much will continue with Avatar 2 and the sci-fi sequel's choice of setting gives Cameron the opportunity to further explore his fascination with the deep, which speaks to his equal fascination with developing the necessary technologies to help "conquer" it.

James Cameron Titanic Set

Arguably the ocean's most prominent appearance in Cameron's filmography came in 1997 with TitanicThe film was lauded for its accurate depiction of the sinking ship, which involved incredibly complex CGI and surprisingly dangerous stuntwork. Ever since that landmark film, Cameron has dedicated himself to underwater exploration, hoping to bring his technology and his findings to the masses. He shared unprecedented glimpses of the RMS Titanic with his 2003 documentary Ghosts of the Abyss, and teamed up with NASA to explore the mid-ocean ridges with 2005's Aliens of the Deep. And then, in 2012, Cameron piloted his very own submarine, the Deepsea Challenger, and led an expedition to the ocean's deepest point. Naturally, Cameron's blend of scientific research and innovative filmmaking has even been the subject of ridicule, perhaps best represented by the classic South Park episode "Raising the Bar," which brilliantly connected the dots between Cameron's inflated ego and his broader cultural impact.

Ultimately, Cameron's obsession with the ocean's depths is rooted in his environmental concerns, which certainly explains the inclusion of his latest technology in Avatar 2, even if Avatar's environmentalism felt rather underwhelming. While the innovative director's obsession with underwater technology can certainly seem excessive at times, there is no denying its potential for science and film alike. And with Avatar 2 already making history, only time will tell what else Cameron has up his sleeve to go beyond the 3D spectacle of its predecessor. If it helps it become a similar success with audiences, Cameron's intrepid spirit will have paid off in ways beyond satisfying his creative and scientific curiosity.

Next: Avatar 2 Needs More Than Its Record-Breaking Underwater Gimmick