The Marvel Cinematic Universe is a well-oiled machine, and it's been on a serious roll with Phase Three. Every single blockbuster in the current slate of movies has been a critical and box office hit. This includes Anna Boden and Ryan Fleck's Captain Marvel, which was the final movie to arrive in theaters before Avengers: Endgame broke records and delivered countless plot twists.
Anna Boden and Ryan Fleck did have a lofty job ahead of them, adapting a lesser-known hero's origin story into live-action, while also breaking new ground for the MCU. And as it turns out, the movie really came together in the editing and reshoot process for the duo of directors. As Boden recently explained to CinemaBlend's Eric Eisenberg:
That aspect of it is always one of my favorite parts of filmmaking. I love being in the edit room. I love being surprised by how you can put together what you shot in different ways that have it really create different feelings and mean different things. And it was amazing to be working with these other two talented editors who have their own way of looking at things. So, of course, it developed over the course of editorial, and really I find it's not like you're re-writing it. It's more like you're figuring out how to tell the story that you thought you were telling, and didn't actually tell the way the way that you... if you just put it together in a very literal fashion, you realize that you didn't tell the story that you you thought you were telling, and now it's about retelling it so that you are telling the story that you initially came up with, if that makes sense. And part of that process is just putting it in front of an audience and seeing if they're feeling what you want them to feel at the moment that they should be feeling things.
Anna Boden makes a great point. Movies are primarily a visual medium, so it's easier to craft scenes and the overall narrative of them once there's footage to manipulate. And since blockbusters like Captain Marvel come with reshoots built into the schedule, there's the ability to include additional footage to move the storytelling forward.
In her conversation with Eric Eisenberg, Anna Boden also directly references test screenings as an integral part in the filmmaking process for Captain Marvel. Having actual eyes watching drafts of the movie allowed the narrative to be fine-tuned, and changes to be made that might help the movie become more user friendly. Its an effort that worked, as Carol Danvers' origin story made a ton of money at the box office.
In the same conversation with CinemaBlend, Ryan Fleck also the true help that Marvel's reshoots schedule was in the making of Captain Marvel. As he put it:
That is unique to Marvel. They plan out the reshoots after every movie they make. For us it was like Anna was talking about - it was just clarifying the story, making sure the audience is understanding. I mean look, we're dealing with something called the Supreme Intelligence, which is a very complicated entity, a very complicated character. So we just needed to make sure that what the character was saying and that her interactions with Carol Danvers were really just, instead of adding confusion of the story, we're helping clarify the story. So I think that we added a few lines here and there between Carol and the Supreme Intelligence that helped clarify that story.
Getting Annette Bening was a major get for Captain Marvel, and the American Beauty actress ultimately played two separate characters: The Supreme Intelligence and Mar-Vell / Dr. Wendy Lawson. In order to make sure the audience could follow these mysterious figures, additional scenes were shot that could give appropriate exposition.
Captain Marvel made a big splash in her solo movie, and popped up as a supporting character in Avengers: Endgame. While not involved in the Time Heist, her powers were a macguffin for multiple plot points, and she was shown crossing over with Earth's Mightiest Heroes. Kevin Feige has teased that she'll have a major role in Phase Four, although the studio is still keeping its cards close to the chest.