Jason Momoa Spills Major 'Aquaman' Spoiler, Explains Idea Behind Red Carpet Haka

Jason Momoa slipped up and spilled a major "Aquaman" spoiler during his appearance on "The Late Late Show," quickly explaining that this is why he kept trying to defer questions to his costar Yahya Abdul-Mateen II.

Yahya, though, wasn't totally clear-headed either because he was sharing the stage with one of his first-ever childhood crushes in Julia Roberts. After joking about what a motley crew the four of them made, including James Corden, things quickly settled into the type of joyous chaos you'd expect from such disparate personalities.

The trio had a lot of fun on the couch, at least until Jason dropped his "Aquaman" bombshell and stunned everyone -- including himself -- into silence. Elsewhere, he talked about how they decided to incorporate a traditional Haka dance into their premiere red carpet experience and shocked Julia with his Christmas tradition.

You never know when a spoiler might drop. It must be one of the most difficult things about promoting a film considering these actors and actresses know everything that's going to happen in the film. They must constantly remind themselves that the audience knows nothing, and what constitutes a spoiler.

To put it bluntly, Jason pulled a Tom Holland with this reveal, which came up during a fairly innocent conversation about all the intricate stuntwork that went into his choreographed fight scene with Yahya's Black Manta. Julia was stunned to find out it took four days to film what will be five minutes in the final cut.

According to Momoa, though, it wasn't all fighting. Dropping his hand on Yahya's leg, he casually said, "There's a whole emotional scene with him and his father because I kill his dad."

Immediately he knew what he'd done, and seemed shocked at himself. Yahya rocked back in dismay while Julia and James simply sat there with their jaws hanging out. DC may not be as notoriously crazy about spoilers as Marvel is, but there's no way they could be thrilled about such a major reveal.

On the other hand, it might even pique audience curiosity even more. We'd argue that superheroes don't kill, but Superman did plenty of it in his movies. The DC universe of films is a far darker place than either the Marvel Cinematic Universe or their print counterparts.

For the most part, everything seemed to center around Jason. James was over there crushing pretty hard on him, literally swooning when Jason said that he married his first-ever crush. Julia was flexing and showing off her own superhero muscles to the DC Comics star.

Meanwhile, Yahya actually mustered up the nerve to tell Julia, "You were my first human crush. I was five years old and you were Tinkerbell. You were my Tinkerbell. I would clap for you every day."

It was a sweet admission, but for one thing. "I'm just a little bit stuck on the human crush," she said, emphasizing the "human" part. But in all honesty, Yahya had a pretty rock-solid answer for that one. Check that out, as well as Jason Momoa's surprising Christmas tradition that floors the panel in the video above.

Even better than that, though, is how everyone else reacts to how he chose to express it. Let's just say, when James Corden asks you what you do to get into the holiday spirit, don't just answer with a person's name.

In what may go down as one of the most memorable red carpet moments in the history of entertainment, Jason Momoa joined a group of Polynesian men and his children to perform a traditional Haka dance. It was so unexpected, and yet so authentic that it proved a powerful moment that perfectly set up the film.

And it was about more than Jason's Polynesian heritage. "We based the character around Polynesian culture and thought it would be honoring a lot of people by doing it," he said.

That said, though, the Haka has meaning to the Momoas as well, which is part of what made the experience so special for him. "I've made our own Haka for my family and my children were out there with me," he said. You can check out the whole performance in the video below.

To learn more about Momoa's introduction to the Māori Haka you can read this interview with his tutor in the traditional dance.

Much like "Black Panther" incorporated a lot of African traditions into its superhero narrative, it's refreshing to see "Aquaman" also tapping into non-Western cultures for influence, expanding the scope of traditional superhero storytelling to embrace a more global stage.

"Aquaman" swims into theaters on December 21.

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