Eternals director Chloé Zhao detailed how the prime Celestial prevented the heroes from interfering with Thanos' plan.

Zhao spoke to Total Film magazine for its Eternals cover issue and was asked about why the superpowered beings didn't step in to fight Thanos and his army when he came to Earth seeking the Infinity Stones. The latest Eternals trailer discussed Thanos and why the team stayed out of things, and Zhao further explained how the film will confront that issue.

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“[The audience] will understand why,” Zhao told the magazine. "Not only why, but how complicated not interfering made them feel. We explore that. You’ll see that in the film. The Eternals were instructed not to interfere with any human conflict unless Deviants are involved. There’s a reason why that’s the case. And that was the instruction from the prime Celestial Arishem."

In the full trailer for the film, we see Kit Harington's Dane Whitman confront Sersi about the Eternals' lack of involvement with some of Earth's biggest conflicts. She says as much as Zhao, that the Celestials, the creators of the Eternals and Deviants, forbade it unless the latter group was involved. But as Zhao teased, that decision will have ramifications for the characters.

Zhao went on to explain how the new film and its millennia-spanning story allowed her to detail a time before Thanos -- or anyone we know from the MCU -- was alive.

"What excited me is the idea of going back in time, and exploring [the time] before Thanos was born, before anyone was born," Zhao said. "Where does the MCU go back in time? And that brings us to the mythology of the Celestials. Anything involving the Celestials is going to be at a huge scale level of complication, let’s put it that way."

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The director previously talked about Eternals being a standalone film, which will explore the history of the cosmic group. But she also said it will have a major impact on the Marvel Cinematic Universe going forward -- and it's likely that the team will no longer sit idly by when a threat comes to Earth.

To get the full story, check out Eternals in theaters on Nov. 5.

Source: Total Film via GamesRadar+