WARNING: The following article contains major spoilers for Avengers: Endgame, in theaters now.
Brie Larson's Carol Danvers was heralded as the new face of the Marvel Cinematic Universe, and its strongest character, "by far." Her introduction in Captain Marvel, in which she was imbued with the power of the Space Stone, certainly lent credence to the latter, which may led the hero to being sidelined for much of Avengers: Endgame.
Captain Marvel serves as a deus ex machina who conveniently appears when needed. When Tony Stark (Robert Downey Jr.) is at death's door in the depths of space, she rescues him, following through on the hype of the end credits of Infinity War and Captain Marvel end-credits.
But after she brings Tony and Nebula (Karen Gillan) to Earth, she effectively disappears, not only to help other worlds but also to scour the galaxy for Thanos. Other than the exchanges in which she speaks down to the Avengers and then earns Thor's approval, she has little dialogue. The next time she chimes in is five years later, when she participates in video conference call with Black Widow's team, and indicates she'll be busy for some time in space.
It's a big letdown, seeing as the MCU is supposed to shaping her as a leader going forward. We expected more interactions with Iron Man and Captain America, so the baton could be passed. What makes it even more disappointing is she conveniently appears in the final act to take out Thanos' flagship, Sanctuary II. It becomes obvious that, whenever the heroes need someone to out-muscle the Mad Titan, she's the solution. We saw it at the beginning of the film, when she wrangled up Thanos for Thor to behead, and at the end, she pops up to beat him down again, have a moment of glory with her fellow female warriors and then evade Thanos' forces so he can't reclaim the Infinity Stones. But all that does is reinforce her role as deus ex machina.
It's a storytelling problem created by introducing such a powerful character late in the game. Ultimately, with her powers, why does Captain Marvel need the Avengers at all? She's a one-woman cavalry, so the filmmakers have to devise a way to relegate her to the sidelines, especially as they want to focus on the original six Avengers.
However, as we see in Endgame's finale, the 2014 version of Thanos could have gone toe to toe with Captain Marvel, so she didn't necessarily have to be solution, and could have been kept in the plot's "time heist" as someone biding her time. It's all perfectly summed up by the lack of a reunion with Nick Fury, demonstrating the film doesn't have room to flesh out what Captain Marvel establish. Ultimately, all of those issues lead to Carol Danvers' entry into Endgame feeling like a disservice to the character, with her role limited to that of a plot device rather than served as a bridge between the old guard of the MCU and the new.
Directed by Joe and Anthony Russo, Avengers: Endgame stars Robert Downey Jr. as Iron Man, Chris Evans as Captain America, Mark Ruffalo as Bruce Banner, Chris Hemsworth as Thor, Scarlett Johansson as Black Widow, Jeremy Renner as Hawkeye, Brie Larson as Captain Marvel, Paul Rudd as Ant-Man, Don Cheadle as War Machine, Karen Gillan as Nebula, Danai Gurira as Okoye and Bradley Cooper as Rocket, with Gwyneth Paltrow Pepper Potts, Jon Favreau as Happy Hogan, Benedict Wong as Wong, Tessa Thompson as Valkyrie and Josh Brolin as Thanos.