The first trailer for Captain America: Brave New World had plenty in there for longtime Marvel Cinematic Universe fans to dig into, whether it was the brief glimpse at Red Hulk or Giancarlo Esposito's mysterious new character. However, there was one possible easter egg included that has left the internet abuzz since the trailer released and would be the first meaningful reference in the MCU back to the climax of 2021's Eternals.

A Celestial Easter Egg

At several points during the trailer, flashes of a battle over open ocean can be seen as missiles are fired from warships, fighter jets zooming by overhead, and both Captain America and Falcon trying to navigate the chaos. The battle, itself, was not what had many fans online talking, but rather the large objects that appeared to be sticking out directly from the ocean with no surrounding landmass.

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It has led many fans online to speculate that the battle is actually taking place among the exposed, petrified body of the Celestial Tiamut that was last seen in Eternals.

While Tiamat took centerstage during the climax of Eternals, the celestial's impending birth was revealed to be at the heart of the film's entire narrative.

An Eternal Life

Audiences learned over the course of Eternals that Earth, like many worlds before it, was seeded by the Celestial known as Arishem to help give life to a new Celestial. Arishem, itself, explains to the Eternal Sersi that the energy created by highly populated planets is what allows for the birth of new Celestials as part of a universal cycle of destruction and birth. It was also revealed that the Deviants were meant to protect populations from apex predators, but they went against Arishem's programming and began hunting the populations they were tasked with protecting, leading Arishem to create the Eternals. Once the Celestial is born in an event dubbed the Emergence, the Eternals sent to that world have their memories wiped and are sent to the next seeded planet to ensure the population's safety.

Tiamat was revealed to be the Celestial Arishem seeded in Earth millions of years earlier and the Emergence was happening sooner than expected due to the events of Avengers: Infinity War and Avengers: Endgame. Ajak, the Eternals' original leader, learned of this and was formulating plans to stop it when she was betrayed and killed by Ikaris, who was considered the strongest warrior of the Earthbound Eternals.

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Sersi ends up following through with Ajak's original plan to stop the Emergence, though it causes a rift among the remaining Eternals as Kingo decides to stay out of it completely while Ikaris and Sprite try to ensure the Emergence takes place.

Ultimately, Sersi is able to link her consciousness with the other Eternals to enhance her ability to manipulate and transform matter to effectively turn Tiamat to stone and stop the Emergence. Part of Tiamat's head, hand, and shoulder are the only parts that made it to the surface before Sersi could stop him and have since sat exposed in the Indian Ocean and no other MCU films or series have addressed it in any direct manner.

Truth or Speculation?

The potential inclusion of Tiamat's body in Captain America: Brave New World has been a point of speculation going back to 2022, when rumors began to emerge that the film would be the first to directly address Tiamat's halted birth. Additionally, some alleged insiders suggested Tiamat's body would be a central piece to film's conflict as several nations, including the U.S., begin a mad scramble to claim as much of the Celestial's body as they can, most notably the indestructible metal known as adamantium. However, these rumors were never confirmed by Marvel Studios or anyone with direct knowledge of the film's production and narrative.

Brave New World's first trailer, though, does seem to hint there may have been some truth to those early rumors.

It was among these rumors and alleged insider reports that it first came out Harrison Ford's ‘Thunderbolt' Ross would be serving as the U.S. President and later revealed to be Red Hulk. Both were outright confirmed in the first trailer, with Sam Wilson addressing Ross as “Mr. President” and the closing shot of Red Hulk throwing Captain America's shield into the ground. However, only time will tell if the rest of these rumors turn out to be true or simply wishful thinking on some fans' parts.

Captain America: Brave New World is scheduled to release in theaters on February 15, 2025.