Warning: This list contains plot spoilers for Eternals.

The long-awaited Eternals marks many firsts for the Marvel Cinematic Universe. Though the franchise has seen movies on an epic scale in the past, none have done it in such a unique way as the 2021 film. It is a sprawling opus that takes place in real locations, and it juggles 10 different superheroes that are completely unknown to general audiences.

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Though there are just as many fun stories from the movie's development, Marvel Studios taking on such a huge task proved to be challenging in more ways than one. Between erasing characters from the screenplay, struggling with the flying scenes, and an actor wearing his superhero pants backward for an entire month, the production could have gone smoother.

Kumail Nanjiani Was Tricked Into The Bollywood Dance Sequence

Kingo dancing on his movie set in The Eternals

Marvel Studios has made it common practice to cast comedy actors as superheroes, and the latest example of that is having Kumail Nanjiani as Kingo. The character blends in with humankind by becoming a Bollywood movie star, and there's a spectacular dance scene in the movie that shows what a leading man he is.

However, when he was first told about the dance scene, Nanjiani refused to do it, claiming that he can't dance. Director Chloé Zhao obliged and replaced the musical number with a fight scene in the screenplay. But when the actor turned up to set in London, he found out that the fight scene was all a lie, and he found himself in the middle of a Bollywood musical anyway.

Ikaris Was Inspired By Man Of Steel

Ikaris looking stoic in Eternals

It's not often when movies are inspired by films of the DC Extended Universe, especially not the Marvel Cinematic Universe. The MCU is the crowning champion of superhero movies, both in terms of critical reception and box office numbers, and the DCEU has always been playing catch up since its inception.

But Zhao is upfront about how influenced she was by Man of Steel. She talked about how the 2013 movie focused on the humanity and realism in the story, and she applied that to Ikaris when writing Eternals. The director even thought that Terrence Malick had made the movie when she saw the trailer.

Salma Hayek Signed On For More Than One Movie

Ajak emits yellow energy from her hands in Marvel's Eternals.

The iconic Salma Hayek has announced that when she signed on to star in Eternals, she also inked a deal to feature in several Marvel movies too, and she couldn't be more excited about it. The actor said that it was fun being part of a "secret society that you have to protect so fearlessly."

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Marvel Studios has made a habit out of having actors sign multi-film deals. They do this just to be safe, as not every actor who signs a multi-movie deal always has to fulfill the number of projects they agreed to. But the studio generally throws these deals at more up-and-coming actors, which makes Hayek's multi-film deal a surprise, as she's such an established star.

Nanjiani Was Wearing His Costume Pants Backwards For Weeks

Kingo fires an energy blast at a Deviant in Eternals.

Being the joker that he is, Kumail Nanjiani isn't afraid to tell embarrassing stories, and it seems like there's a ton of them from his work on the Marvel movie. There are some great costumes in Eternals, but the ones that the supreme beings wear seem to be a little awkward for when the actors need to go to the bathroom.

Kumail Nanjiani didn't drink water or coffee on set for four weeks because he was too scared to take off the whole costume in the bathroom, as he'd have to assemble it all back together again. But after a month, he discovered that there was a zipper at the back of his pants and that he'd been wearing them back-to-front the entire time.

Why The Movie Was Shot In Real Locations

Ikaris walking through a field in Eternals

Eternals looks a lot different from other movies in the universe, and that's because it's shot in real locations. Audiences can actually see the wind blowing through the characters' hair and them tackling real terrain. Zhao said that the reason for her wanting to approach the movie like that was because she wanted to create an immersive experience and add a "level of realism."

If there was any MCU movie that made sense filming in real locations, it's Eternals. The movie follows the titular cosmic lifeforms as they try to blend in with Earth and humankind, so a soundstage with a green screen behind the actors wasn't exactly going to cut it.

Chloé Zhao Had Some Help From Denis Villeneuve

Denis Villeneuve on the set of Dune 2021

Zhao has been very vocal about her friendship with fellow filmmaker Denis Villeneuve, who has just directed Dune. According to the Eternals director, Villeneuve was there for her when it came to moral support. They supported one another when both of their movies' release dates were pushed back by months because of the pandemic.

The directors are clearly on the same spiritual level, as the two movies are very similar in tone and style. Just like Eternals, Dune is full of amazing action sequences and real locations, not to mention that the cinematography is breathtaking.

Harry Styles Was Zhao's First Choice For Starfox

Christopher Nolan and Harry Styles on Dunkirk set

One of the biggest surprises in the movie comes after the credits have rolled, and it isn't a character's appearance that shocked audiences, but the actor. In the post-credits scene, Starfox shows up, who is played by none other than "Watermelon Sugar" singer Harry Styles.

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Chloé Zhao didn't even consider anybody else for the role, and she was adamant that nobody else could have played Eros. The director explained that she has been fascinated with the singer's acting style ever since she saw him in Dunkirk. And she even went as far as to say that if Styles had turned it down, then she would have scrapped Starfox too.

The Original Script Had Even More Superheroes

All of the Eternals walk through the desert

There are already so many characters and superheroes in Eternals that it's hard to keep track. And on top of that, there are so many questions fans still need answering about the ones who do exist. However, there were almost even more superheroes in the film.

When Zhao first got involved with the development, there were 12 heroes, whereas there are 10 in the final movie. Zhao doesn't mention who those additional two characters are, but they may be introduced in a later MCU movie or even in the inevitable Eternals sequel.

Nanjiani Studied Tom Cruise And Will Smith

Kingo in the desert in Eternals

There are some Redditors who think Marvel fans don't know who Kamail Nanjiani is, but regardless of his popularity, he did a great job of playing Kingo. And part of the reason why he steals every scene he's in is because of how the actor prepared for the role.

To get into character as the famous Bollywood star, Nanjiani says he studied several Hollywood movie stars, most notably Tom Cruise and Will Smith. The actor said that he wanted to find out what made them movie stars and that he wanted to capture their elusive quality.

Richard Madden Didn't Enjoy Filming The Flying Scenes

Ikaris firing lasers from his eyes in Eternals

Though flying is a superpower most kids and even adults wish they could have, Richard Madden, who plays Ikaris in the movie, thinks anything but. The actor thought that shooting the flying scenes was the worst part about working on the movie.

Madden felt self-conscious about himself when shooting the scenes, and they made him rethink his feelings towards his costume, which he originally thought was cool. The actor said that everything looks different when hanging in midair from wires and that he looked like he was wearing blue leggings and nothing else.

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