Credit: Marvel StudiosMarvel Studios is gearing up for a pivotal moment as the Avengers prepare to reunite, marking the fifth chapter in the franchise’s signature crossover series.
After years defined by both cultural dominance and growing scrutiny, the Marvel Cinematic Universe is positioning Avengers: Doomsday (2026) and Avengers: Secret Wars (2027) as a course correction, one that blends legacy characters, Multiversal storytelling, and a surprising shift in who stands at the center of the storm.
The road here has been uneven. While Spider-Man: No Way Home (2021) delivered one of the studio’s biggest box office wins, subsequent releases like Ant-Man and the Wasp: Quantumania (2023), The Marvels (2023), and Captain America: Brave New World (2025) sparked debate about franchise fatigue and long-term vision.
Those questions have only amplified the significance of Marvel’s decision to bring back Joe and Anthony Russo, the directors behind Avengers: Infinity War (2018) and Avengers: Endgame (2019), as well as Captain America: The Winter Soldier (2014) and Captain America: Civil War (2016).
The Russos are returning to helm both Doomsday and Secret Wars, and both they and Marvel Studios president Kevin Feige have described the films as more than sequels. Instead, they’re being framed as a reset point—one meant to redefine the MCU’s priorities and power structure heading into its next saga. This next chapter is set up to be the long-awaited Mutant Saga.
Doomsday, set for release on December 18, 2026, is shaping up as one of the studio’s largest ensemble efforts yet. The cast spans longtime MCU anchors like Chris Hemsworth’s Thor and Anthony Mackie’s Sam Wilson/Captain America, as well as more recent additions such as Florence Pugh’s Yelena Belova and Pedro Pascal’s Reed Richards/Mister Fantastic.
The movie will also pull heavily from outside Marvel Studios’ original continuity. Characters and performers from 20th Century Studios’ X-Men era–like Patrick Stewart’s Charles Xavier/Professor X–are now firmly in play, underscoring how central the Multiverse has become to Marvel’s storytelling.
Perhaps the most enticing casting decision, however, belongs to Robert Downey Jr. After defining the Infinity Saga as Tony Stark/Iron Man and besting Josh Brolin’s Thanos in Endgame, Downey is returning in Phase Six as Victor Von Doom—Doctor Doom—one of Marvel Comics’ most formidable antagonists.
The character was first teased in the post-credits scene of The Fantastic Four: First Steps (2025), as he engaged with Franklin Richards, and early speculation paints this version of Doom as something more complex than a traditional villain.
Current theories suggest Doom may operate in morally ambiguous territory, positioning himself as a rival power rather than a simple adversary. One popular line of speculation centers on Doom pursuing Steve Rogers (Chris Evans), driven by the fallout from Rogers’ time-travel actions in Avengers: Endgame. While Marvel has yet to confirm any of this, the studio has clearly leaned into mystery as a marketing strategy.
That strategy was on full display during a widely watched livestream in early 2025, often referred to by fans as the “chair reveal.” The presentation rolled out a sprawling cast list that included Sebastian Stan (Bucky Barnes/Winter Soldier), Paul Rudd (Scott Lang/Ant-Man), Simu Liu (Shang-Chi), Tom Hiddleston (Loki), and Vanessa Kirby (Sue Storm/Invisible Woman), while also confirming the Multiverse-heavy X-Men involvement.
Notably absent from that reveal were several longtime MCU figures.
Mark Ruffalo, for example, won’t appear in Doomsday; he is expected to return in Destin Daniel Cretton’s Spider-Man: Brand New Day, dated for July 31, 2026. Other missing names—Brie Larson’s Captain Marvel, Ryan Reynolds’ Deadpool, and Hugh Jackman’s Wolverine—have fueled ongoing speculation about who may be held back for Secret Wars or later reveals. It was recently confirmed that Reynolds is actively pursuing Deadpool 4.
Marvel later added fuel to the fire during the theatrical run of Avatar: Fire and Ash (2025), attaching teaser spots for Doomsday that spotlighted Steve Rogers, Thor, the X-Men, and Wakandan characters encountering Ben Grimm/Thing (Ebon Moss-Bachrach). Evans’ appearance in those previews confirmed that his Captain America remains part of the larger plan.
Plot details remain closely guarded, but leaks and insider chatter have offered glimpses of what Marvel may be building toward. According to MyTimeToShineHello, as reported by Comic Book Movie, the film could open with a Multiversal confrontation involving legacy characters from different Marvel eras.
“Apparently, the movie will open with Maguire’s web-slinger battling the X-Men, ‘and particularly Hugh Jackman’s Wolverine,'” Comic Book Movie writes. “This somewhat corroborates claims we’ve heard about an Incursion destroying Sam Raimi’s Spider-Man Universe, and it gives Maguire’s Peter Parker a lot to fight for in this movie and Avengers: Secret Wars as he looks to bring back his loved ones.”
The same source made bold claims about the film’s scale.
“Avengers: Doomsday is not only the most epic Avengers movie, but it might be the most epic movie OF ALL TIME,” they wrote (via Comic Book Movie). “The opening scene alone tops any previous Avengers movie, and the final battle is just INSANE.”
Marvel Studios has not verified these reports, and they remain firmly in rumor territory. Still, with the film positioned in the lucrative December corridor—a window that recently delivered a $1 billion-plus run for Avatar: Fire and Ash—the studio is clearly betting big.
Additional claims suggest Doom initially aligns himself with the Fantastic Four to confront reality-threatening Incursions, only for his true motivations to emerge.
“Victor asks the Fantastic Four for help with the Incursions. They travel together with Steve Rogers to the MCU in their ship to warn everyone, then join forces to head to the X-Men universe–the source of the next Incursion that will destroy their Earths,” MyTimeToShineHello writes, via Comic Book Movie. “They have a plan to fix everything.”
“The scooper adds that the movie will see Steve Rogers and Thor teaming up to seek out Loki, presumably meaning they’ll need to find him and the TVA as part of their likely doomed (pun intended) plan to save the Multiverse.”
There are so many theories abound, but the question remains: will Doomsday be good enough to draw the masses back into theaters and recreate the lucrative performance of the previous Avengers movies? Well, according to insiders, the response after early screenings is “good.”
“It’s still very much in post. Let me see if I have anything on that. I did check in before the show, just in case. I did get a little something. Avengers is in post, and they still have a lot of pick-ups to do, but the buzz is good. The buzz is good. You’re going to like it,” Jeff Sneider said on The Hot Mic. “You’re going to like the movie.”
The reported early reactions come as the Doomsday production heads head into reshoots this spring ahead of filming for Avengers: Secret Wars. As Geek Tyrant says:
While previous reports claimed Avengers: Doomsday reshoots were scheduled to begin in April, recent photos indicate production may have started early in London. No cast members were spotted, but crew wearing Avengers: Doomsday jackets were seen filming scenes staged in what appears to be World War II era London.
There’s no clear indication who these scenes involve or what exactly is being filmed. Steve Rogers and Peggy Carter immediately come to mind, but it could just as easily be an alternate reality sequence or even a quick establishing shot tied to the Multiverse storyline.
Beyond the films themselves, Marvel has been quietly expanding Doom’s presence. An animated short tied to Marvel Super Heroes: What The–?! offers a playful tour of Latveria, complete with Doomstadt landmarks, Doombots, and an amusement park dubbed “Doomland.” The segment leans into humor while still reinforcing Doom’s authoritarian grip on his homeland.
Will this be the version audiences see in December 2026?
What’s your reaction to these Avengers: Doomsday developments? Share your thoughts with Inside the Magic in the comments.