No one (probably) ever said that filming a movie that takes place mostly underwater would be easy. In an interview with The Hollywood ReporterAquaman director James Wan explained the challenges that the film's setting has posed to its production.

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"It's a very technically challenging shoot to be on," Wan said on the phone as he made his way to the film's Australia set. "Working with water, and even the dry-for-wet sequences are very complex... Our equivalent of two people sitting around chatting in the underwater world is super complicated. You have to think about CG with the hair, and how their clothing moves, how are they floating, what kind of rig we put them on and all that stuff."

Wan went on to explain that his desire to avoid CGI and shoot using real actors is one of the main reasons that this challenge is occurring. "That just makes it very difficult and time-sucking and time-challenging to do all of this," he said. "So it's not an easy shoot — but hopefully it will pay off in spades down the line."

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In July, footage of Aquaman debuted at Comic-Con International in San Diego. While it has been revealed that the Hall H footage will remain exclusive to SDCC, there's a chance that much of it will appear in upcoming teaser trailers, especially with Aquaman set to appear in the upcoming Justice League movie.

Few details are known about the plot of Aquaman, but Wan has promised a "swashbuckling action-adventure, sort of high seas adventure story" in the vein of 1980s classics like Raiders of the Lost Ark and Romancing the Stone. He's also teased that it's "ultimately a quest story," but has yet to reveal what the object of that search might be. Chronologically, the film is set after the events of Justice League, so there's the possibility that the Mother Boxes will play a role.

recent set photo featuring Mera, played by Amber Heard, teased the possibility that the movie could delve more into her character's revised origin, in which she's a princess of Xebel, a mostly forgotten extra-dimensional penal colony for an ancient group of separatists banished by Atlantis behind a sealed portal.

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Arriving Dec. 21, 2018, Aquaman stars Jason Momoa as Aquaman/Arthur Curry, Willem Dafoe as Nuidis Vulko, Amber Heard as Mera, Patrick Wilson as Ocean Master, Yahya Abdul-Mateen II as Black Manta, Temuera Morrison as Thomas Curry, Dolph Lundgren as Nereus, Nicole Kidman as Atlanna, Ludi Lin as Murk, and Michael Beach as Jesse Kane.