Eternals is a 2021 American epic superhero film based on the Marvel Comics race of the same name. Produced by Marvel Studios and distributed by Walt Disney Studios Motion Pictures, it is the 26th film in the Marvel Cinematic Universe (MCU). The film was directed by Chloé Zhao, who wrote the screenplay with Patrick Burleigh, Ryan Firpo, and Kaz Firpo. It stars an ensemble cast including Gemma Chan, Richard Madden, Kumail Nanjiani, Lia McHugh, Brian Tyree Henry, Lauren Ridloff, Barry Keoghan, Don Lee, Harish Patel, Kit Harington, Salma Hayek, and Angelina Jolie. In the film, the Eternals, an immortal alien race, emerge from hiding after thousands of years to protect Earth from their evil counterparts, the Deviants.

Movie Explained : SPOILER Alert!!!
In 5000 BC, ten human-like Eternals from the planet Olympia are equipped with superpowers and sent by the Celestial Arishem to Earth, where they are supposed to fight the invasive Deviants. Over the millennia, they protect humanity from the dangers posed by these creatures, but are not allowed to interfere in the development of the world’s population. After the supposedly last Deviants are killed in 1500, there is a break within the group, as opinions differ about their responsibility towards the people. They spend the next five hundred years mostly separated from each other, waiting for Arishem to send them back to their home planet.
In the present day, Sersi and Sprite live together in London. After Sersi was left by her partner Ikaris over five hundred years earlier, she now has a relationship with Dane Whitman, who works at the Natural History Museum. When the trio is attacked by the Deviant Kro one evening, Ikaris appears and chases the monster away. Sersi, Sprite, and Ikaris then decide to reunite all Eternals in order to be prepared for the renewed danger. Only Ajak can no longer join the group as she was previously killed by a Deviant.
As the former leader of the group, Ajak gave Sersi the ability to communicate with Arishem. In a conversation with the Celestial, the latter reveals that the primary mission of the Eternals was not to fight the Deviants, but to prepare Earth for “The Emergence.” Arishem explains that for millions of years, the Celestials have been planting their seeds in populated planets so that a new Celestial can be born from them. Since the energy of innumerable individuals is required for this, the Celestials sent the Deviants, to destroy the top predators of the planet and thus ensure the development of life. However, the Deviants evolved and became top predators themselves, which is why the Eternals were sent to fight them. As Arishem explains, Earth has now reached the necessary population so that the Emergence—the birth of the Celestial Tiamut and the resultant destruction of the planet—can take place.

Since the Eternals have learned to love humanity over the millennia, they decide not to obey the will of Arishem and instead prevent the emergence. Through the “Uni-Mind”—a connection between all Eternals created by Phastos that unites their powers—Druig plans to get the necessary power to put Tiamut to sleep by means of mind control. However, not all Eternals are satisfied with the plan: while Kingo leaves the group because he does not want to face Arishem, Ikaris reveals himself as a secret opponent. It was he who had been informed of the emergence by Ajak centuries before and who killed her when she too spoke out against the destruction of Earth. Sprite joins Ikaris’ side because of her one-sided love for him.
After Makkari locates the place of emergence at the foot of an active volcano, there is a fight between Ikaris, Sprite, and the Eternals. Kro, who wants revenge on the Eternals and previously killed Gilgamesh, is also present. Together, the group brings Ikaris under control, while Druig knocks Sprite out and Thena defeats Kro. Phastos activates the Uni-Mind, which Ikaris also surprisingly joins after he reconsiders his life on Earth and his relationship with Sersi. Since Druig is too weak from the previous fight to face Tiamut, Sersi, who manipulates substances, takes on the task and turns Tiamut into ice, killing it. Plagued by feelings of guilt, Ikaris then flies towards the sun. Sersi, who still has the Uni-Mind, gives Sprite the ability to age like a human.
The team parts ways, with Thena, Druig and Makkari flying into space on their spaceship Domo to find other Eternals and to win them over to their cause. Sersi, Phastos, Kingo, and Sprite continue living on Earth as their home. However, the former three are teleported into space by Arishem and warned that because they disobeyed his orders, he will return for judgement.
In a mid-credits scene, Thena, Makkari and Druig are visited by Eros, an Eternal and the brother of Thanos, and his assistant Pip, who offer their help. In a post-credits scene, Whitman opens an old chest inherited from his ancestors that contains the legendary Ebony Blade, while an off-screen voice asks him if he is ready for it.