From the wonder and discovery of Arthur, to the strength and determination of Mera, to the relentless anger of Black Manta, Aquaman is full of remarkable characters, all with their distinct motivations and desires. Yet, while the heroes and villains of the newest DCEU movie may steal the spotlight, particularly in the most recent posters, at the heart of the film is something equally important and distinct.

The kingdom of Atlantis.

It’s as much a part of the story and world of Arthur Curry as his trident and power over sea life. Aquaman is a tale of coming home. However, when it comes to this unique superhero, “home” is like nowhere on Earth…or in any existing superhero movie.

“I’ve been wanting to make a design movie for the longest time,” says Aquaman director James Wan. “That was part of what I really enjoyed about this character. Not only do I get to revamp this underdog character, but I also get the opportunity to design the different worlds visually and create the different kingdoms. I’m a big fan of world creation.”

While last year’s Justice League had a scene set in Atlantis, the movie took a minimalist approach to what was shown, keeping most of the kingdom off camera. That meant Wan and his production design team had few restrictions when it came to designing the legendary undersea kingdom.

“One of the things that I really want to capture with the civilization of Atlantis is that it’s a bit of new and old,” Wan reveals. “We’re all familiar with the legend of Atlantis—that they’re such an advanced race of people and culturally far ahead, but they became too powerful for their own good. They created something and they sank as a result of that.

“I took a lot of that mythology and played with it. Even though Atlantis is now a civilization under water that has been around for a long time—hundreds of years—they’re very technologically advanced. Socially, they’re very advanced. Yet, in other ways, they’re somewhat archaic. They still have a that they’re very true to. They have a very rigid way of looking at things.”

That rigidity, along with their isolation and dependence on the sea, has led to a major distrust of the surface world—something that has existed for years in the Aquaman comics. Most Atlanteans don’t visit the surface, meaning all they know about the world above is what they’ve been told. Of course, the arrival of Arthur—a half-Atlantean who grew up on the surface—throws a wrench into what they believe.

“They’re a race of underwater people and they don’t usually come up here that much,” explains Wan. “They don’t like us and what we represent, so they have no desire to come up here. They’re not accustomed to surface world traditions. They have their own traditions.”

Coming up with those traditions, and the culture that spawned them, is part of the process when you’re designing a fantasy world. Often, the best fantasy has its roots in reality—think of Tolkein being inspired by European history and Neil Gaiman looking to myths and folklore when creating the world of The Sandman. In designing Atlantis, Wan looked towards our world and society, but also beyond it, into the realms of nature and, yes, monster movies. (Wan’s background is in horror, after all.)

“I was a big fan of Toho and giant kaiju movies growing up,” he shares. “I’m a big fan of Godzilla. I love Gamera. All of the magic and wonder of those scary, wonderful creatures that Ray Harryhausen created. I tried to bring a bit of that sensibility into here, and it works perfectly because the different races of people have that kind of look. I haven’t really shown you the monsters in this, but it definitely plays heavily into the film. They’re a big part of this world that Arthur gets to explore.”

When asked about the different races, Wan continues, “You hear a lot today about diversity in films, and casting a diverse cast. I love the idea that in this world, I can actually go even further and show us all of the different ethnicities and races in the different kingdoms.

“There are seven kingdoms in the underwater world. a handful of the kingdoms where they look more like normal humans—like you and I. But then there are other kingdoms. You’ve seen in the trailer that there’s one where they’re all merpeople. Then there’s another kingdom—the Brine Kingdom—where they’re basically all giant crustaceans. They’re big crab men and women. I thought it would be really fun to lean into that. Then, of course, the other kingdom is the Trench, which are these monsters. Obviously, a lot of this is heavily inspired by what Geoff Johns did for the New 52.”

Wan and his team put just as much time and effort conceiving the kingdom as they did its people, something that started with realizing an underwater city would never be built like a land-based one. It also wouldn’t resemble our underwater constructions. Don’t look for the pressure-resistant steel and piping you see in submarines and in movies like The Meg and The Abyss. The buildings in Aquaman were constructed by people who have lived their entire lives underwater.

“The concept is when ancient Atlantis sank, they ‘grew’ new Atlantis on top of it,” says Wan. “Structurally, I’ve tried to think of what construction underwater would look like. There would be no steel or wood. No metal. The way I believe they would do it is how coral is made. They grow corals. So, buildings are grown like corals. Just from that, it really informs what the visuals would be.”

Aquaman is a movie that takes you somewhere you’ve never been before, made all the more remarkable by the fact that it’s set on our world. The myth of Atlantis has persisted for thousands of years for good reason—with so much of the ocean unexplored, who can say Atlantis couldn’t actually exist?

“The thing that I really like best about it is that I get to create this big, fantastical world, but it’s not like we’re going to visit these magical worlds in outer space or in another dimension,” Wan shares. “It’s taking place right here on Earth. I think that’s the coolest thing. We’ve explored so little of the ocean. We’ve explored space more than we have explored the ocean, so the idea that there could be this massive civilization of beings is super exciting to me.”

Aquaman arrives in theaters on Friday, December 21, 2018. For more on the upcoming DC blockbuster, click here.