The hardest part of any superhero movie is getting the titular comic book character right. In many cases that means making sure the costume looks perfect, so when it comes to Aquaman, both Jason Momoa and Director James Wan took special care to make sure Arthur Curry looked his best.

Momoa explained at a press junket for Aquaman that he already felt like the titular character back when he was filming Justice League. He recounted a moment on set where he was "sitting there staring at [Ben] Affleck and Wonder Woman," before screaming into the microphone, "I'm sitting on a Batmobile. This is the coolest thing ever!"

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Despite feeling like he had become the character,, however, he still had to look the part. It's the Aquaman solo film that will finally put Arthur Curry in his iconic orange and green costume, and considering it's such a big deal, the production team put a lot of work into making him look perfect.

James Wan admitted, "One of the biggest visuals I wanted to get right was the costume. And that is something we definitely worked hard and long on to try and really nail down." It's fitting, then, that Momoa's memory of wearing the costume for the first time is of Wan's sense of accomplishment.

The actor remembered not having a mirror to look at himself, so he looked to his director to get a sense of his reaction. "[He] looked like a kid when he beamed, like, 'I did it,'" Momoa recounted. "He was super proud, and he didn't say anything. I could just see it on his face. It was a really beautiful moment."

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On a more personal level, the film's star also revealed that he showed the costume to his kids during a FaceTime chat. "They were like [gasp], and their eyes were just blown away."

Directed by James Wan, Aquaman stars Jason Momoa as Aquaman, Amber Heard as Mera, Patrick Wilson as Ocean Master, Willem Dafoe as Nuidis Vulko, Yahya Abdul-Mateen II as Black Manta, Temuera Morrison as Thomas Curry, Dolph Lundgren as Nereus and Nicole Kidman as Queen Atlanna. The film opens on Dec. 21.