Avatar 2 is on its way to theaters after an eleven-year wait, but what is known about the sequel’s ambitious underwater scenes? Released in 2009, Avatar may not have won any awards for originality when it came to plot, but the sci-fi adventure movie did wow audiences worldwide and break all manner of box-office records thanks to its stunning visuals. From the behind-the-scenes set photos that have been released here and there, the sequel looks to be even more visually ambitious than the original.

Like any groundbreaking achievement in CGI, it’s difficult to encapsulate what made James Cameron’s alien planet eco-adventure so impressive upon release. Avatar featured more immersive and realistic settings than any earlier movie had achieved through the use of CGI, and its seamless integration of human and computer-generated characters was considered incredible at the time. The techniques used in the production of Avatar have since become commonplace in blockbuster cinema, but Cameron has a slew of new tricks and tech to utilize in Avatar 2.

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The sequel will see much of the original cast return to the verdant world of Pandora to pick up where Avatar’s happy ending left off, and the long wait between installments is mostly down to Cameron and company experimenting with new technology and methods of filming, which weren't available until the last few years. The ambitious underwater sequences of Avatar 2 proved particularly problematic for actors and crew alike, as Cameron made the unusual decision to film these sequences entirely underwater instead of adding water digitally in post-production as is often the norm.

Avatar 2's New Underwater Mo-Cap Technology Explained

Avatar 2 James Cameron Underwater

Although little is known about the plot of Avatar 2, fans of the films will be happy to hear that on-set photos have at least revealed some details of how the movie’s new motion-capture technology will work. The long-awaited sequel’s motion-capture tech is a far cry from the often-unrealistic and weightless 3D animation seen in cinemas when the first Avatar arrived on-screen in 2009, and with any luck, the resulting footage will be incomparable to the likes of 2009’s A Christmas Carol or 2007’s uncanny valley nightmare Beowulf from Back to the Future's Robert Zemeckis. The big technological advancement this time around is James Cameron’s approach to filming underwater scenes, as Avatar 2’s many underwater sequences will eschew the traditional route taken by the likes of Aquaman where the production shoots on a green screen soundstage and digitally adds water in post.

Aware of how water affects weight, and heavily invested in realism, Cameron is instead insisting on shooting sequences underwater and using new cameras developed specifically for this purpose in the production of the Avatar sequels. To avoid the water’s surface reflecting uneven light, the creators of Avatar 2 covered the surface of the water in the production's many tanks with floating balls. Cameron's underwater mocap suit technology is not unlike standard mocap attire, but features an added face-mounted camera to ensure the actors' subtle facial expressions aren’t missed. It’s an ambitious new way of shooting underwater, and one which asks a lot of both previously unseen technology and the movie’s large, all-star cast.

Kate Winslet Broke Tom Cruise's Underwater Record Filming Avatar 2

Avatar 2: Kate Winslet’s Underwater Scene Is Part Of A Na’vi Ceremony

One new addition to the cast of Avatar 2 is Cameron’s Titanic star Kate Winslet, and the newcomer had something of a baptism of fire during filming for the big-budget sequel. Winslet held her breath for a staggering seven minutes while filming an underwater scene for Avatar 2, comfortably beating an already-incredible record set by Tom Cruise during the filming of Mission Impossible: Rogue Nation. As Avatar 2’s story remains shrouded in secrecy, there’s precious little known about the character Winslet will be playing, with many fans suggesting that the length of this feat suggests she’ll be taking on the role of an underwater-dwelling Pandora native. However, until more is revealed about the story of Avatar 2 there’s no way to know for certain who (or what) Winslet is playing, although the news that the screen veteran managed to outdo Cruise’s lung-popping record is already a promising development.

Winslet's Avatar 2 Underwater Scenes Are A Na'vi Ceremony

Jake and Netyri under Ewa's tree

One thing prospective viewers do know about Winslet’s Avatar 2 character is that she will take part in a Na’vi ceremony at some point in the sequel’s action. According to Winslet, her seven-minute underwater scene took place as part of what will be a Na’Vi ceremony in the finished film, although the actor was careful not to reveal whether her character will be a human, a Na’Vi, or a new previously-unseen life form. According to the glimpses fans have seen, Winslet’s character appears to have large wings and seems to be doing a ceremonial dance, but until viewers see more than mere on-set glimpses, all these guesses remain in the realms of speculation.

Related: Why Avatar Sequels Will Be Bigger For Disney Than Star Wars Movies

Sigourney Weaver Also Filmed Underwater Scenes For Avatar 2

Sigourney Weaver held her breath for 6 minutes during Avatar 2 filming

Not to be outdone, original Avatar star Sigourney Weaver also filmed underwater scenes for Avatar 2, with Cameron’s Aliens star returning to the franchise despite her Avatar character (spoilers) dying before the close of the first film in the series. Despite recently entering her 70s, the formidable Weaver undertook the same diving training as the rest of Avatar 2’s cast to be able to film lengthy underwater sequences for the sequel.

What The Avatar 2 Underwater Scenes Mean For Its Story

Jake and Neytiri hold each other in Avatar

It’s almost impossible to tell what the story of Avatar 2 will hold for fans of the franchise, as the details of the sequel’s plot remain a mystery to the public. That said, the knowledge that the movie will feature lengthy underwater sequences such as Winslet’s Na’vi ceremony, combined with Cameron’s assertion that the Avatar sequels will focus on the larger world of Pandora, suggests that Avatar 2 will feature a more immersive look at Pandora’s culture, ecosystems, and society.

Although the first film was dismissed by some critics as “Dances With Wolves meets The Smurfs” thanks to the simplicity of its story, Avatar has recently undergone something of a revival online among fans who enjoy the simplicity of its pro-environment, anti-capitalist story. Popular podcast Chapo Trap House recently praised the movie’s unapologetically direct anti-war message, and Cameron’s promise that Avatar 2 and its subsequent sequels will further flesh out the world of the Na’vi as they continue to resist occupation by greedy, uncaring humans suggests that the director will likely be returning to this pointed critique of fossil fuel production and the endless invasions that pay for it. By focusing on the splendor of Pandora’s nature, Avatar 2's story looks likely to make Pandora a more realistic and recognizable setting while also reinforcing the first film’s theme of preserving ecosystems instead of exploiting them.

More: Avatar 2's Biggest Hurdle Is What Made The First Movie So Successful

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