Avengers: Infinity War's director promises that while the film is going to feature a massive roster of heroes, it will keep the focus on an important few. Ever since it was announced, Marvel fans have known that Infinity War was going to be the MCU's biggest film yet; it's the payoff of nearly a decade's worth of easter eggs, references, and overt teasing, seeing Earth's Mightiest Heroes showdown against stone-hungry Mad Titan Thanos.

This was proven early last year when Joe Russo stated he and co-director brother Anthony were working with a set of 67 characters, meaning the film is essentially bringing together every wing of the sprawling MCU so far. With promises of such epic scale, however, come concerns of overstretching. The Russos have proven themselves as being able to juggle characters in Captain America: Civil War, but that was primarily a Steve Rogers film; how do you decide who to focus on for such a mega team-up?

Screen Rant got some time to chat with director Joe Russo during last week's San Diego Comic-Con about this balancing act and learned some clues about who the film is going to revolve around.

Screen Rant: We’ve heard rumors that there are 60+ MCU characters in the film. Who does the story really center around in Infinity War?

Joe Russo: You know, the story really centers who you would expect it to center around, so our more important characters. This is a culmination film ten years in the making and we are pulling the main story threads from all of the different franchises into one unifying narrative. So any of the important characters are going to be in this film and they are going to have something important to do in the movie.

It would seem the directors are more than aware of any concerns about the massive cast and, as they did with Civil War, are ensuring the movie's singular story is centered on a few main platers. Balance is an important part of any ensemble film, especially so when you're dealing with such defined characters. The Avengers managed to keep things stable, but that had only six key players; Age of Ultron upped that to nine (more counting cameos) and many fans feel showed the wear. By keeping the core cast tight and the supporting one sprawling, Infinity War should avoid those pitfalls.

That Russo said the central heroes were "important" and would tie together the main story threads from the past decade, that would seem to indicate they're talking about the MCU's founding icons: most likely Iron Man, Captain America and Thor. This has been expected for a while given how it's likely to be Robert Downey, Jr. and Chris Evans' final turns in their respective roles and that the new poster from SDCC put them front-and-center. It had originally been suggested these long-standing heroes would be held back for a later film, although that came before the related nature of Avengers 3 and 4 became known and the actors' contracts were renegotiated to allow their appearances.

Of course, there's also the new generation of heroes to consider - Doctor Strange, Spider-Man, Black Panther and Captain Marvel (although she was recently said to not be in Avengers 3 at all) - who can also be considered important - especially Spidey, who was prominent in the D23/SDCC footage. These comments could indicate that they won't come into full prime position until Avengers 4 a year later.

All this said, we have actually known who the "main character" of the film is for months now, a factor that shows where the movie's real focus lies: as Kevin Feige said at the start of production, Infinity War is all about Thanos.

Next: Will Marvel Release The Avengers: Infinity War Teaser?

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