For a while, the party line on the possibility of an ‘Iron Man 4’ was that it was not going to happen. And, at least technically, that’s still true—because instead Robert Downey Jr. is co-starring ‘Captain America: Civil War,’ where his Tony Stark and Chris Evans’ Steve Rogers will get into an epic superhero tussle.

Explaining the reasoning for making a ‘Captain America 3’ instead of an ‘Iron Man 4,’ Downey discussed the project with Empire (via Collider):

They said to me, ‘If we have you, we can do this, or ‘Cap 3’ has to be something else.’ It’s nice to feel needed. And at this point it’s about helping each other, too. I look at it as a competition and I go, ‘Wow, maybe if these two franchises teamed up and I can take even a lesser position, with people I like and directors I respect, maybe we can keep things bumping along.’

Downey also hinted at the origins of the wedge that comes between the two Avengers:

The main thing to me is, what sort of incident could occur, and what sort of framework could we find Tony in? The clues about where we might find him next are in ‘Ultron.’ But what would it take for Tony to completely turn around everything he’s stood for? Joss brings this up all the time. It’s kind of weird that these guys would have all these throw downs all over planet Earth and yet when the movie’s over, nobody minds. What would the American government do if this were real? Wouldn’t it be interesting to see Tony doing something you wouldn’t imagine?

In the comics, the ‘Civil War’ storyline grew out of an incident where a group of young and untrained heroes accidentally caused a massive catastrophe, prompting Tony Stark (who was closely aligned with the government at that time) to lead the call for superhero registration while Steve Rogers, a defender of personal freedom to the end, opposed it. We’ll see how that gets translated to the screen, but clearly elements of it will be very different. And then maybe they’ll make ‘Iron Man 4’ anyway. ‘Captain America: Civil War’ opens in theaters on May 6, 2016.

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