WARNING: This post contains MAJOR spoilers for Eternals.

Mere hours after the world premiere of Marvel's Eternals, the casting reveal in the post-credits scene has been leaked online. Debuting in theaters in just over two weeks, Eternals is the latest movie to arrive from the MCU's Phase 4. It's directed by recent Oscar winner Chloé Zhao and boasts a star-studded ensemble that includes Gemma Chan, Richard Madden, Angelina Jolie, Salma Hayek, Don Lee, Lauren Ridloff, Kumail Nanjiani, Brian Tyree Henry, Lia McHugh, Barry Keoghan, and Kit Harington. In the Marvel universe, the Eternals are a group of cosmic beings with incredible abilities who have been tasked with protecting humanity from the Deviants.

On Monday night, Eternals held its world premiere in Los Angeles. Though reviews are still under embargo for the next week, early reactions for Eternals have made their way online, and they're so far largely praiseworthy. Many appreciated the epic scope of the movie and insisted it is unlike any Marvel project that has come before. It's also said the post-credits scenes for Eternals are not to be missed, though one major surprise has already been revealed.

Related: Eternals Explains Why The MCU Dropped Thanos' Origin Story

Matt Donnelly, a writer for Variety, took to social media following the Eternals premiere and revealed that Harry Styles has been cast in the MCU as Eros, the brother of Thanos. Little else was revealed about his role or what the post-credits scene includes. However, one can assume this means Styles will play a pivotal role in the MCU going forward.

Harry Styles in Dunkirk

Styles has been rumored for the part of Eros for some time now, but Marvel has remained quiet about the possibility. The singer made his feature film debut in Christopher Nolan's Dunkirk, and he has a pair of eagerly-anticipated releases coming up next year: Olivia Wilde's Don't Worry Darling and My Policeman with Emma Corrin. With a Marvel role now under his belt alongside his previous awards fare, Styles is turning into a bona fide movie star.

Eros, also known as Starfox in the comics, is often seen as the polar opposite of his power-hungry brother Thanos. He has similar abilities to the Eternals and has been a part of both that team and the Avengers. It will be quite interesting to see how the MCU incorporates Eros into future movies, particularly since Thanos has already met his end. As always, the post-credits scenes for Marvel movies give just a hint of what's to come, so those going to see Eternals shouldn't expect to see much of Styles' Starfox. However, he's bound to stick around for a while, and more information about his role could emerge once the movie releases. Fans better stay tuned.

More: Who is Marvel's Starfox? Thanos' Eternal Brother Explained

Source: Matt Donnelly/Twitter

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