Jason Momoa
Jason Momoa, pictured July 22, 2017, and his 'Aquaman' movie are facing complications on set. Getty Images

Warner Bros. Pictures' upcoming D.C. Comics venture "Aquaman" is facing difficulties with its shoot, according to The Hollywood Reporter. "Aquaman," which will star Jason Momoa in the title role, has been in production since May but it's slated to make its theatrical debut in December 2018.

Could difficulties potentially delay its big-screen release? On Thursday, director James Wan told the entertainment news publication that the film has proved to be "very technically challenging" to shoot.

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"It's a very technically challenging shoot to be on," Wan told THR. "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."

A representative for Warner Bros. did not immediately return International Business Times' request for comment.

Wan revealed that the challenges primarily stem from his desire to utilize the film's stars as much as possible because he intends to only use CGI when necessary.

"That just makes it very difficult and time-sucking and time-challenging to do all of this. So it's not an easy shoot — but hopefully, it will pay off in spades down the line."

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The film has already been hit with delays. Deadline broke the news December 2016 that an "Aquaman" movie was expected to hit theaters October 2018, but it received a two-month delay. There had previously been an unconfirmed July 2018 release.

Wan explained to Cinemablend that limitations on special effects have prevented the film from going into production until now.

"There’s a reason why they’ve never made a movie about this until now, because technology has never allowed us to tackle something this complicated."

According to IMDB.com, "Aquaman" has an estimated budget of $160 million—a modest figure compared to the first installment of previous superhero films. "Spider-Man: Homecoming" cost a reported $175 million to make, "Man of Steel" required $225 million and "Green Lantern" cost $200 million.

The budget is also surprising considering the film involves quite a bit of underwater shooting, which is also a big reason why the "Avatar" sequel has been pushed back. Director James Cameron told MTV News in 2011, "We have to figure out how to do performance capture underwater, which has never been done."

"Aquaman" follows Arthur Curry upon his discovery that he's the heir to Atlantis, the underwater kingdom. His superpowers include swimming at supersonic speeds, communicating with other sea life and manipulating ocean tides. Along with Momoa, actors Willem Dafoe, Amber Heard, Nicole Kidman, Dolph Lundgren and Patrick Wilson have been cast in major roles.

Wan's familiarity with the movie franchise arena may make him the best man to bring Arthur Curry's story to life. "Furious 7," "The Conjuring" and "Insidious" are just a few directorial efforts under his belt. He also served as a producer for "Annabelle" and several titles within the "Saw" franchise.

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