A new video has emerged online showing Dolph Lundgren practicing underwater stunts for the upcoming Aquaman movie. Aside from starring in Sylvester Stallone's The Expendables series, Lundgren has mostly appeared in direct-to-video movies in recent years. Last year, though, he made an exception and appeared in a recurring role on The CW's Arrow as the villain Konstantin Kovar. And now, he'll be returning to the DC Universe in a different fashion next year, playing Nereus, the king of the sea nation Xebel, in James Wan's Aquaman movie.

After his brief tease in Zack Snyder's Batman V Superman: Dawn of Justice last year, Jason Momoa's story as Aquaman officially begins later this year in Snyder's Justice League, which sees the Atlantean King join forces with the rest of the world's finest heroes: Superman (Henry Cavill), Batman (Ben Affleck), Wonder Woman (Gal Gadot), The Flash (Ezra Miller), and Cyborg (Ray Fisher). Momoa will then return to headline his standalone movie next year, in which Lundgren also stars.

Aquaman's principal photography officially began last month in Australia, though it's possible that production has temporarily gone on hiatus so that the film's leading star can head back to England to undergo reshoots for Justice League. Meanwhile, Lundgren has been busy practicing underwater stunts for his role as King Nereus, as seen in a new video posted on Twitter this morning. Take a look:

Aside from the fact that the upcoming superhero movie is adapting Aquaman onto the big screen for the first time, one of the toughest obstacles facing the production team is filming people talking and interacting underwater. In Batman V Superman, Snyder had Momoa film his cameo in an actual water tank, and audiences could clearly see the actor holding his breath. Snyder opted for a different approach in Justice League, using CGI instead of actual water. It looks like Wan is utilizing the same approach for Aquaman -- and we see that in the above set video.

At this point, though, it's unclear how involved Nereus will be in the story. Unlike most of the characters appearing in the Aquaman film, Lundgren's character is relatively new to the DC Universe. Nereus made his debut only four years ago during the publisher's New 52 reboot, specifically in Aquaman Vol. 7 #19 in 2013. Long before Nereus became King of Xebel, the underwater colony that Mera (Amber Heard) hails from, he was one of the nation's strongest warriors.

He became the nation's king after Mera's father, the original King of Xebel, had died, and he took Mera to be his wife, as is dictated by their customs. However, comic book fans know that Mera is the devout lover and companion of Arthur Curry, aka Aquaman, which is something that may cause trouble in the upcoming film. There's also the possibility that Nereus considers himself to be the rightful ruler of Atlantis, considering the fact that Atlantis and Xebel once were united as one kingdom. We'll just have to wait and see how all of this unfolds in next year's Aquaman movie.

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Source: Twitter