Marvel's Mr. Fantastic Replacement Officially Announced

Published Sep 29, 2026, 1:15 PM EDT Lewis is a Lead Writer for Screen Rant and has written for the site since 2022. This has allowed Lewis to explore a vast array of films, TV shows, books, comic books, and games from across the mainstream world of pop culture, reflecting his lifelong love of all media and typifying his experience in the world of fiction storytelling. To top this off, Lewis graduated from Northumbria University with First Class Honours in Film & TV Studies, truly exemplifying his experience in the medium. The Marvel Cinematic Universe has confirmed who and how Mr. Fantastic will be replaced going forward. As far as upcoming Marvel movies are concerned, Reed Richards is expected to have a big role in several of them. In 2025, the ending of The Fantastic Four: First Steps set up the team's role in two massive MCU projects, Avengers: Doomsday and Avengers: Secret Wars. This made sense to anyone familiar with Marvel Comics, with the primary villain of those movies, Doctor Doom, being intrinsically tied to Marvel's First Family. The recent release of Avengers: Endgame Encore, an extended version of the 2019 movie, was meant to connect directly to Avengers: Doomsday, especially for Marvel characters like the returning Steve Rogers, Loki, and Bruce Banner. As a result, Mr. Fantastic and the rest of The Fantastic Four were left absent, leading many to wonder how exactly the team will factor into Avengers: Doomsday's story. Moreover, instead of putting minds at ease and confirming that Reed Richards and Doctor Doom will have their classic comic-book dynamic in the film, Avengers: Doomsday's directors confirmed Mr. Fantastic's MCU replacement in this sense. During an interview with Empire, via AvengersUpdates, Anthony and Joe Russo confirmed that the tease of Doom creating his mask from Avengers: Endgame Encore was intentionally created to emulate Tony Stark's creation of Iron Man: “There is certainly a symmetry [between Iron Man and Doom] at play here. There is an interesting examination of good and evil at play.” Given that Robert Downey Jr. plays both characters in the MCU, this makes sense, but it leaves many wondering where Reed Richards fits into this. From what is known about Marvel Comics and past Fantastic Four stories, if a dichotomy between good and evil is being built using Doctor Doom and another Marvel character, the latter should be Mr. Fantastic, or at least a member of The Fantastic Four like Sue Storm. Outside of glimpses from Avengers: Doomsday's trailers, nothing indicates that Reed and Doom will have their rivalry play out in the MCU, especially since the upcoming film is crafted to contrast Doom with Tony Stark. As many feared, Tony Stark is Mr. Fantastic's MCU replacement. A Big Worry About RDJ's Doom Casting Is Coming True When Robert Downey Jr. was announced to be playing Doctor Doom in the MCU, it was met with skepticism. Of course, RDJ is an excellent actor, one who could easily pull off the complexities of a character like Doom. However, the actor's MCU legacy, links to Tony Stark, and sheer star power as a result led many to worry that he was cast as Doom with these aspects in mind, as opposed to being truly right for the role. The MCU has a history of replacing Marvel Comics characters with Tony Stark, such as when he created Ultron in 2015's Avengers: Age of Ultron in place of Hank Pym. If, beyond a few scenes or lines in Avengers: Doomsday, the film distanced Doom from Tony Stark, these worries would have been eased somewhat. That said, the aforementioned quote from the Russos and the parallel being drawn between Tony Stark and Victor Von Doom confirm otherwise. As it turns out, RDJ's Tony Stark is replacing Mr. Fantastic as Avengers: Doomsday's antithesis to Doom due to his former role, legacy, and popularity as Iron Man. Marvel Has Another Chance To Make Mr. Fantastic As Important As He Should Be Although the confirmation of Iron Man and Doom's contrast in Avengers: Doomsday somewhat sidelines Reed Richards, Marvel still has the chance to make him important going forward. 2027's Avengers: Secret Wars is expected to be set solely on Battleworld, a plane of existence created as a result of Avengers: Doomsday's incursions. Expectedly, this movie will somewhat shrink the focus onto a smaller cast of characters, just as Avengers: Endgame did, before exploding in the final act. If this is the case, Reed Richards could take more of a key role. After all, the 2015 comic run of Secret Wars featured Reed in a massive role, as he took on Doom directly in an attempt to save the universe. Hopefully, the Marvel Cinematic Universe will follow this storyline, allowing Mr. Fantastic to shine as the good to Doctor Doom's bad, regardless of Tony Stark being positioned as such in Avengers: Doomsday. Release Date December 18, 2026 Runtime 165 Minutes Director Anthony Russo, Joe Russo Cast Reed Richards / Mr. Fantastic Vanessa Kirby Sue Storm / Invisible Woman Writers Stephen McFeely, Michael Waldron, Chris McKenna, Erik Sommers Producers Anthony Russo, Joe Russo, Kevin Feige, Louis D'Esposito, Jonathan Schwartz Prequel(s) Spider-Man: Brand New Day Sequel(s) Avengers: Secret Wars Franchise(s) Marvel Cinematic Universe, The Avengers, Fantastic Four, Black Panther, Thor, X-Men