Take reception out of the mix, and Avengers: Infinity War will probably be the biggest duology in film history. It will be the culmination of 18-20 films dating back to 2008. Where do you even start? How do you begin and what are the limits?

Collider’s own Haleigh Foutch spoke with screenwriters Christopher Markus and Stephen McFeely at the Captain America: Civil War junket and while they obviously couldn’t give us any specifics on the film, they did give us an insight into their process. In addition to telling us that they’re close to being done on their first draft and that scripts for both movies are due at the end of April, they also told us what led up to the creation of those two screenplays:

STEPHEN MCFEELY: We got back from Atlanta after spending all of our off-time in Atlanta brainstorming, and then got back to Atlanta and spent the last four months of the year in a room, sometimes with the Russo Brothers, and almost always Jeremy Latcham, who was on all of the Avengers movies, and Nate Moore, who was our guy on Winter Soldier and Civil War, and just brainstorm, brainstorm, brainstorm. It looks like a serial killer’s lair with all of the cards and stuff on the walls. CHRISTOPHER MARKUS: And gradually it begins to take shape, and gradually one thing becomes a story. Now how we can we surprise people? People know the villain. People know the stones and stuff, so it is a little more known than the other movies we’ve done. MCFEELY: We’re starting a little less from scratch. MARKUS: But then what do you do with all of that? How much acid are we expecting the audience to take? MCFEELY: But just how Winter Soldier is not Winter Soldier, and Civil War is not Civil War. They’re not direct interpretations. We take the best ingredients and make a different little meal out it.

By the time we finally reach Infinity War, the MCU may have undergone some radical changes. In 2016 alone, it will be Avenger vs. Avenger plus we have Doctor Strange introducing magic. On some level, the screenwriters are going to be working on faith that the films that come before Infinity War will get the audience on board with the characters and concepts they’ll be using. However, it will still be a “weird” movie:

MARKUS: This is weird, what we’re writing now. It will be less weird a year from now or two years from now because the audience will have seen a few different things. MCFEELY: In the vaguest possible way we have no limits. Limits come with budget and schedule and people going “That’s a bridge too far,” but at the moment anything we have the rights to is possible, and that’s the appeal of this project and the MCU is we can pluck as needed from the comics and from the movies. Like William Hurt—we need someone who represents the government and has a grudge against superheroes and we need this character anyway. Oh! It’s one of the greatest actors in history! Let’s get him!

So with no limits and a huge platform, the expectations couldn’t be higher for Infinity War and Part 1 is still two years away. But judging from the positive reaction to Civil War (read a lot of them here), these writers along with directors Joe and Anthony Russo are more than up to the challenge.

Avengers: Infinity War – Part 1 opens May 4, 2018. Avengers: Infinity War – Part 2 opens May 3, 2019.

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