Anthony and Joe Russo recently spoke with io9 while promoting Captain America: Civil War and discussed their upcoming work on Avengers: Infinity War Part 1 and Part 2.
On the feel of the two parts (Anthony): “The movies are very very different from one another. It’s not a part one and part two scenario, necessarily. They’re just two different expressions. I think it creates a misconception that we’re shooting them at the same time.”
On the two films (Joe): “There’s an overarching story that’s going to be told through all four films. And I think having the amount of characters we have in [Civil War] certainly prepares us to deal with probably triple the amount of characters in Infinity War.”