Ever since the announcement of Captain America: Civil War, we’ve been curious about how the Russo brothers will begin to adapt Marvel’s Civil War comic book story line for the big screen, kicking off a major new arc in the MCU (and one that sees Spider-Man swinging in with a crossover). According to Robert Downey Jr., the seeds for Civil War have already been planted in Avengers: Age of Ultron, once again proving just how much planning and foresight goes into the creation of the MCU.

Captain America: Civil War will pit Steve Rogers/Captain America against Tony Stark/Iron Man, inspired by Marvel’s Civil War comic, which had the two heroes facing off over the Superhuman Registration Act — a government sanction that requires all superheroes reveal their true identities for the safety of the public. That’s the basic premise, and one that will be the basis for Captain America: Civil War.

In a new interview with Empire, Robert Downey Jr. talks about Avengers: Age of Ultron, and how Joss Whedon’s upcoming sequel has some set-up for Civil War:

The main thing to me is, and this is where I think the Russos are quite brilliant and where Kevin backed the play, is what sort of incident could occur and what sort of framework could we find Tony in? The clues are in “Ultron” about where we might find (Tony) next. But what would it take for Tony to completely turn around everything he’s stood for, quote-unquote, because he was the right-wing guy who could still do his own thing….There’s always the bigger overarching question, that Joss brings up all the time – it’s kind of weird that these guys would have all these throw downs all over planet Earth and it looked like a little collateral damage happened over there, and yet when the movie’s over, it’s like nobody minds. You have to figure, ‘Were you to ask the question, what would the American government do if this were real? Wouldn’t it be interesting to see Tony doing something you wouldn’t imagine?

The scope and impact of Ultron’s threat can’t be underestimated — and perhaps it’s this very world-rattling threat that sparks a change in Tony. When asked if Tony would be the villain of Civil War, Downey Jr. had a very thoughtful response:

I wouldn’t put it that way. Ultimately it’s Steve’s story; it doesn’t say ‘Iron Man 4: Civil War’. I think that’s great too. I think Chris [Evans] has been hungry to bring even more of an underside and some shadow to that. I remember the comics – on the surface you got the sense that Cap was baseball and apple pie, but underneath there was all this churning stuff of being a man out of time. Now we know he’s made his peace with that. What’s the bigger issue? It can have a little something to do with the past, but it can be about someone becoming more modernized in their own conflict.

In the Civil War comics, Steve Rogers is opposed to the Superhuman Registration Act, which he finds to be invasive and decidedly unpatriotic, while Tony surprisingly supports it. Regardless of which side you’re on, we can all agree that Captain America: Civil War is going to deliver one hell of a kick-off to this new arc in the MCU, and we can’t wait to see Chris Evans and Robert Downey Jr. square off on May 6, 2016, which is also when Spider-Man will reportedly make his MCU debut.

Until then, we still have Avengers: Age of Ultron, which hits theaters on May 1.

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