Fans Marvel at epic Avengers climax

"That's just the beginning, but it's very exciting for us at Marvel Studios to be able to do a long-form series and really tell many more stories than we can with the movies. Also, these shows will tie into the movies in a way that has never been done before," explains Feige.

Endgame is the second film in history to be shot entirely with IMAX cameras, meaning that IMAX screenings can present the film with up to 26 percent more screen area than standard theaters, thus providing a more immersive experience.

However, the Russo brothers also believe the stories for theaters and those on the streaming service will not outshine each other. "The two of them will interweave in a way and feed each other, moving forward," says Joe Russo.

Feige, the tightly-scheduled studio boss who has a constant stream of meetings and works 11-hour days, has an ambitious blueprint.

"Now we can put anything on the screen thanks to technology, but that still is only a tool to tell a story," he says, concluding: "We have worked on the next five years. We know what movies we're going to make."