Warning: This story contains MAJOR SPOILERS for Captain America: Civil War.

Elizabeth Olsen, Chris Evans, and Sebastian Stan in Captain America: Civil War. Marvel Studios

Captain America: Civil War features one of the largest principal casts ever assembled for a Marvel Studios film, especially one centered around a single titular superhero. And, unlike every other movie in the Marvel Cinematic Universe to date, these superheroes are not battling with an external enemy, but among themselves. On top of that, two significant new superheroes to the MCU set to launch their own movie franchises in the coming years — Black Panther and Spider-Man — are introduced in Civil War, the latter after an unprecedented and frankly miraculous negotiation between two rival movie studios.

Which is to say that making Captain America: Civil War was a Hulkulean task for directors Joe and Anthony Russo. In late April, BuzzFeed News sat down with the brothers — who came up in the industry directing comedies like 2002’s Welcome to Collinwood and 2006’s You, Me and Dupree, and TV shows like Arrested Development and Community — to understand how they pulled together one of the largest and most challenging superhero movies yet.

“We knew that we had to surprise the audience in some way, and to subvert the standard structure, which was tiring us.” Producer Nate Moore, screenwriter Stephen McFeely, director Anthony Russo, screenwriter Christopher Markus, and director Joe Russo on the set of Captain America: Civil War. Zade Rosenthal / Marvel Studios

The Russos’ first Marvel Studios movie was 2014’s Captain America: The Winter Soldier, which is widely considered to be among the very best of Marvel Studios’ movies (if not the best). Months before it opened in April of that year, Marvel Studios chief Kevin Feige was so confident in The Winter Soldier that he began preliminary meetings with the Russos — along with producer Nate Moore, and screenwriters Christopher Markus and Stephen McFeely — to discuss a third Captain America movie.

“[It was] a very soft conversation of us sitting down and just discussing generally what we could do with the character moving forward,” said Joe Russo. “We batted around a bunch of different big ideas. He’s a tricky character, because he’s very stoic and moral. However, we felt like if we kept pushing him, and deconstructing him, we could end up in a place that was very interesting.”

“We knew that we had to surprise the audience in some way, and to subvert the standard structure, which was tiring us.”

The team circled the idea of basing their story on Civil War, a 2006 Marvel comic series by Mark Millar that pits Cap (Chris Evans) against Tony Stark (Robert Downey Jr.) as ideological opposites after the government attempts to place superheroes under its expressed control. The dilemma for the Marvel Studios brain trust was whether Civil War — in which a vast number of superheroes align either with Cap or Tony — was more of an Avengers movie than a Captain America movie.

“The way we answered the question was, of course it could be made into Captain America film if the story is told from his point of view, and if the plot is incredibly resonant with his world,” said Joe. “What’s interesting about Cap is that he had two family units, one from the past, and one in the present. What would happen, we thought, if you took those two family units and we smashed them into each other, and he was forced, on a very elemental level, to choose?”

For Cap’s original family from the 1940s, there was only one choice: his best friend and surrogate brother, Bucky Barnes. Bucky’s transformation into the brainwashed Hydra assassin the Winter Soldier made him a wanted man across the globe, but by the end The Winter Soldier, Cap had dedicated himself to finding Bucky and helping him to reform.

“Cap’s devoted to the idea that there is still a human being inside the Winter Soldier that he knows and loves,” said Anthony. “And he’s going to find that human being in there, no matter what it costs him. How do you put an equally compelling idea up against that?”

The answer: What if Bucky, under orders from Hydra as the Winter Soldier, had secretly killed Tony Stark’s parents, Maria and Howard Stark, who was one of Steve’s closest allies during World War II? “You wind up with a very combustible situation,” said Joe. “In fact, that’s why we decided to do Civil War, because of that idea.”

By setting two of the MCU’s biggest heroes against each other in a third-act battle about a deeply personal conflict — rather than averting yet another global cataclysm — the Russos saw the potential to shake the movie free of an all-too familiar superhero movie trope. “As filmmakers, you have to look to how crowded the marketplace is becoming,” said Joe. “As a fan, there are the things that I’m growing weary of about the [superhero] genre. We knew that we had to surprise the audience in some way, and to subvert the standard structure, which was tiring us.”

There was just one catch. “Kevin [Feige] was like, ‘OK, you guys gotta get Downey!’” said Anthony with a laugh.

Robert Downey Jr. and Chris Evans in Captain America: Civil War. Zade Rosenthal / Marvel Studios

Wooing Robert Downey Jr.

Making a Captain America movie was not part of Robert Downey Jr.’s overall contract with Marvel Studios, so the Russos were tasked — with Feige’s support — with persuading the actor to sign on to the project. The stakes were high: Without Stark, Civil War was a no-go.

According to the Russos, it turned out that what had so excited them creatively about Civil War excited Downey, too. “I think he loved the fact that we were going to deconstruct the genre by having a third act where the two heroes are having in essence a life-or-death battle with each other,” said Joe. “He was really attracted to the fact that we were going to make his character much darker in this than he had been in any other film up to this point.”

Indeed, while Downey’s face is as prominent as Evans’ in the Civil War posters, the fact that this was a Captain America movie afforded Downey an unusual opportunity, one the Russos first experienced at the onset of their career. “[George] Clooney had a small role inWelcome to Collinwood, and he kind of helped the movie get greenlit by doing that,” said Anthony. “We said to him, ‘Oh, thanks so much for doing this role, sorry it’s so small.’ And he goes, ‘Look, guys: This is the most fun for me. Playing the lead kind of sucks, because your job as a leading man is to show up and let everybody else steal the scene. Now I get to steal the scene. That’s really fun for me.’ I think Downey had a bit of that. Because Chris was the titular lead of the film, he had license to go off the rails a little more than he would as a typical lead.”

But that did not mean that Downey was content to coast through the making of Civil War. The actor’s involvement was officially announced at a Marvel Studios media event in October 2014, and right up through production, Downey met regularly with the Russos and screenwriters Markus and McFeely — none of whom had worked on a film involving Tony Stark — to develop the character of Iron Man in Civil War. “There’s a process you go through with Robert where you work on the scenes the week leading up to shooting them,” said Joe. “Whatever scenes are coming up, we’d go over to his house on a Sunday, we’d all have lunch together, and work on the scenes. We would rewrite them based on ideas that Robert had about the character, because he knows the character better than any of us ever will.”

Introducing Black Panther

As the Russos were busy nailing down Downey in mid-2014, they were also developing theCivil War script with Markus and McFeely, and they soon realized that while pitting Captain America and Iron Man against each other was creatively exciting, it also came with its own set of complications. “We knew the movie was going to get binary,” said Anthony. “It’s Cap versus Iron Man, and the two sides versus each other.”

“We wanted to avoid getting in a rut,” added Joe.

“We thought a nice way to shake up that dynamic as the movie progress is if we had this, like, third-party radical, who was tied into the plot in a very propulsive way, but didn’t give a shit about either side of the argument,” continued Anthony.

Enter T’Challa, aka Black Panther, Marvel’s first black lead superhero. “At that point, Black Panther was a movie that Marvel probably wanted to do, and we were like, ‘Well, if you are going to do it, here’s why Black Panther would be really valuable in this movie [too],’” said Anthony. For Civil War, the filmmakers decided that T’Challa would initially believe that Bucky is responsible for the death of his father, and cautiously side with Tony, but his methods — and mere presence — would disrupt the dynamic among the established Avengers. “We loved how he could mess everything up as the story progresses,” said Anthony.

Casting Chadwick Boseman — known for his terrific performances as Jackie Robinson in42 and James Brown in Get on Up — in the role was something of a no-brainer. “He has that great combination that you always look for: He has leading man looks and presence, but with character actor chops,” said Anthony. At that October 2014 press event — at which Feige also announced a Black Panther movie — Boseman stood between Evans and Downey, a visual cue representing his ambiguous role in Civil War.

In the comics, a different character finds his loyalties torn between Cap and Iron Man. But getting him in their film at all plunged the Russos into a most tangled web.

Capturing Spider-Man

Even with Black Panther playing the free radical in Civil War, the filmmakers still felt their movie needed to avoid getting too weighed down by the personal baggage Cap and Tony were bringing to it. “Especially when you’re making movies this expensive, you have to hold a large audience,” said Anthony. “You’ve got to make stories that are well-rounded. We knew how dark we wanted to take the storyline between Cap and Tony, but how do we balance this movie so that it’s not, like, just a brutal experience? We needed some people in this movie who are not invested in the conflict that is tearing this family called the Avengers apart. And we needed one on each side. That’s how we circled Ant-Man and Spider-Man.”

Ant-Man, of course, was already a part of the MCU; Paul Rudd debuted as the character in the eponymous Marvel Studios film in July 2015. The movie rights to Spider-Man, however, were held by a completely different film studio, Sony Pictures — and in the spring of 2014, Sony was gearing up to release The Amazing Spider-Man 2 in the first weekend of May. And yet, according to the Russos, that was also around the time they first floated the idea to Feige of somehow getting Spider-Man into Civil War.

“He was like, ‘Uhhhh, I don’t know? Maybe there’s something there,’” recalled Anthony with a chuckle. “It was like the smallest door was opened to a road forward potentially.”

“We had to behave in such a manner as if there were no other options for the movie than to have Spider-Man in the film.”

Thus began a nearly yearlong creative process for the Civil War filmmakers, in which they had to craft their film on the (at first) faint promise that two rival corporations might somehow figure out how to share an enormously popular and lucrative superhero character in a deal unheard of in Hollywood since Mickey Mouse and Bugs Bunny shared a scene in 1988’s Who Framed Roger Rabbit? And yet, by the summer of 2014 — after The Amazing Spider-Man 2opened to tepid reviews and less-than-stellar box office — the Russos said they were given enough of a sense that including Spider-Man in Civil War was genuinely possible. So, they forged ahead as if it was a fait accompli.

“We had to behave in such a manner as if there were no other options for the movie than to have Spider-Man in the film,” said Joe.

“[We] worked Spider-Man into the story in a way that is inexcisable, or else the house falls down and you’ve got to rebuild it again,” added Anthony. “We were very exposed on a creative level of needing him. … Even after the preliminary agreement was made to share Spider-Man, there were tons of deal points that still needed to be worked out. So even though we got permission to keep proceeding as if Spider-Man was in the movie, it was always like, don’t talk about it, keep quiet about it, because it was still very sensitive.”

The Russos give full credit to Feige for hammering out the Spider-Man deal with Sony, which was officially announced in February 2015 and includes a new Spidey film, Spider-Man: Homecoming, produced by Feige and Marvel Studios and released by Sony on July 7, 2017. “Kevin loves Spider-Man, and he’s always been looking for a way to [use] him,” said Anthony. But the brothers were not above exercising their own leverage to keep the deal alive. “Certainly there’s a lot of pain in executing a deal like that, and when people feel pain, they go, ‘Ah, is there a way to relieve this pain by just not doing this deal?’” said Joe. “They would come to us and say, ‘Are you sure we can’t make this movie without Spider-Man?’ We would say, ‘You absolutely can’t do it without him.’ And then we would cite the tone.”

“‘The whole movie falls apart!’” added Anthony. “But it was true.”

“It was absolutely true,” said Joe. “The movie, I think, does become a much more dour affair without the addition of Spider-Man.”

In Civil War, Tony Stark visits Peter Parker (played by Tom Holland following an exhaustive casting search) after catching YouTube videos of the teenager exercising his powers for the first time. “It made sense to us that Tony wanted to recruit this kid because he’s incredibly strong,” said Joe. “But he always has an amazing nonlethal way of stopping people, which is he webs them up. So in Tony’s mind, he’s like the perfect nonlethal weapon to bring to a fight.”

“The other thing we loved about Spider-Man is that he’s a kid,” added Anthony. “Everybody else was so experienced; they’d been through adventure after adventure. So we were like, let’s take the greenest version of Spider-Man — the kind of kid who’s just starting to use his powers, but he wasn’t the whole package yet. So that let Tony really become a mentor for him. We loved that relationship.”

Subverting expectations and preparing for Infinity War

The actual villain in Civil War, Zemo (Daniel Brühl), drew his name from the Marvel comics, but was otherwise radically transformed into a grieving Sokovian soldier who holds the Avengers responsible for his family’s death during the events of 2015’sAvengers: Age of Ultron.

“Zemo is not necessarily anything other than a conduit in the movie. He’s an allegorical villain. He doesn’t really do anything, other than, at a very crucial moment, open a can of worms in front of them when tensions are high,” Joe said, referring to Zemo’s reveal to Tony that Bucky killed his parents, sparking the wrenching climactic fight between Cap and Iron Man. By keeping the antagonist in Civil War so comparatively mortal and low key, the filmmakers hoped to further upend what audiences have come to expect from a superhero movie.

“We knew that we could give people a movie that is like, oh, Captain America, who’s the lead of the movie, isn’t going to fight the bad guy in the end of the movie,” said Anthony. “Even Iron Man, who’s the second lead, isn’t going to fight the villain. In fact, the guy who’s going to fight the villain, Black Panther, isn’t even going to fight the villain — he’s just going to keep the villain from killing himself.” (As for the obvious narrative parallels between Civil War and the recent Batman v Superman: Dawn of Justice, the Russos pled ignorance. “We knew nothing about the project,” said Anthony. “I think it was dangerous to our process to try to guess about what they might do.”)

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