Marvel Studios will bring back almost every Marvel Cinematic Universe actor whose character plays a role in Disney+'s upcoming What If...? animated series.As revealed at Disney's D23 Expo, What If...? will boast almost the entire MCU's roster. For instance, Hayley Atwell will reprise the role of Peggy Carter for the short where her character receives the super soldier serum instead of Steve Rogers.RELATED: What If: First Look at Peggy Carter's Captain Britain, Revealed

The panel revealed one short will see Steve Rogers become Iron Man. Another will explore the Marvel Zombies storyline in a horror-themed alternate reality tale. Since the series will bring back MCU actors, this suggests Chris Evans could return to voice Captain America once more, despite his insistence that he was done with the role after Avengers: Endgame.

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The show is based on the Marvel Comics series of the same name. The episodic What If...? comic book offers readers a look at what the Marvel universe may have looked like had certain key moments in its history played out differently. With Jeffrey Wright's Watcher as a curator of sorts, the animated series will show viewers the direction the MCU's world may have taken had the scales of fate been tipped. The series is comprised of 23 episodes, one for each MCU movie.

Marvel's What If...? does not currently have a release date. The animated series slated to arrive on Disney+ sometime during Summer 2021.