Leaks and rumors spoiled some key Avengers: Doomsday plot details that Marvel Studios doesn't want fans to know. Production on the long-awaited Endgame sequel took place in the UK from March to September last year, with reshoots expected to occur in the coming months before one of the MCU's biggest blockbusters ever finally arrives on December 18.
As usual for an Avengers epic, Marvel Studios hasn't confirmed much about Doomsday since announcing most of its main cast ahead of filming. Fans know the movie will introduce Robert Downey Jr. as Doctor Doom, set the stage for 2027's Avengers: Secret Wars, and bring back the classic X-Men actors, but much beyond that is a mystery, at least in an official capacity.
Tobey's Spider-Man vs Hugh's Wolverine
Avengers: Doomsday is rumored to open with a dramatic face-off between Tobey Maguire's Spider-Man and Hugh Jackman's Wolverine, finally fulfilling decades of hopes from fans for the Marvel Legacy heroes to share the screen.
This scene will supposedly, according to MyTimeToShineHello (MTTSH), come "while their Earths are about to crash into each other," immediately establishing the danger of the Incursions that will be threatening the Multiverse.
Other rumors claimed that Spider-Man and Wolverine won't be alone in this face-off for the fate of their universes. The Adamantium-infused mutant may be backed up by other members of the X-Men, while Alfred Molina's Doc Ock could tag along with the wall-crawler, having returned a new man after Spider-Man: No Way Home.
Doctor Doom's Agenda (& Steve Rogers' Role)
Fans have been well aware for some time that Robert Downey Jr.'s (RDJ) Doctor Doom will be portrayed as the main character of Avengers: Doomsday. In fact, it appears the MCU's latest big bad will even ally himself with the other heroes of the Multiverse in the hope of stopping the Incursions.
Avengers 5 is reportedly making some changes to Doctor Doom's backstory, not least of which is the addition of his wife and child, who were killed in an accident that also scarred him, explaining why he wears his iconic mask.
Ultimately, Doom "traced the cause of the accident" to the events of Avengers: Endgame and, most notably, Chris Evans' Steve Rogers travelling back in time to live out his peaceful life with Hayley Atwell's Peggy Carter.
Marvel Studios will reunite two of its original stars with a twist as Doomsday reportedly filmed scenes in the past featuring Rogers and Carter (who now have a baby), as well as RDJ's Doom. It's unclear whether Doom is aiming to confront or recruit the retired Avenger, as he may be hiding his agenda for the time being.
While Doom is guising himself as the Multiverse's one true savior, he is reportedly on a "revenge quest" with a "vendetta against the Multiverse," hunting down those who have caused Incursions.
Cyrptic HD Quality described Doom's role in the 2026 blockbuster as a "wolf in sheep's clothing," who unites with Earth's Mightiest Heroes with "seemingly noble intentions." However, eventually, he will be revealed to have "ulterior motives" that will become apparent by the time the credits roll.
The Fantastic Four & Doctor Doom Team-Up
Continuing his string of Avengers: Doomsday leaks and rumors, MTTSH claimed that Robert Downey Jr.'s Victor von Doom will turn to the Fantastic Four for help dealing with the Incursions. The start of that meeting was ominously depicted in The Fantastic Four: First Steps' post-credits scene.
The scooper added that Pedro Pascal's Reed Richards and RDJ's Doom "have a relationship" in the MCU, settling fears that their history would go ignored.
Thunderbolts* already revealed what follows this meeting, showcasing a "space crisis" that sees the Fantastic Four's ship landing on Earth-616. It now seems that both Marvel's First Family and Doctor Doom will be aboard that ship, along with, somehow, Chris Evans' Steve Rogers, says MTTSH.
Doomsday's fourth trailer, showcasing the meeting between M'Baku and The Thing, may indicate that the Fantastic Four will land in Wakanda, from which Shuri could employ the rest of Earth's Mightiest Heroes for help.
The X-Men Incursion
Having joined forces, the Earth-828 ensemble will travel to Earth-616 to warn of the oncoming Incursions before teaming up to venture over to the X-Men universe. The Fox world is said to be "the source of the next Incursion" that they must resolve before their own reality is obliterated by it.
Those who stayed through The Marvels' credits will know that Monica Rambeau has found herself on the X-Men's Earth, which many have speculated could be causing the Incursion with Earth-616. The WandaVision star reportedly could have a major role in Doomsday, but many scoopers are adamant that actress Teyonah Parris has yet to film any scenes and won't until reshoots (if at all).
Fourteen years after the Avengers vs. X-Men comic event made waves and kickstarted hopes for a live-action adaptation, Marvel's two premier superhero teams will face off in Doomsday, perhaps orchestrated by the titular villain.
Doomsday's third trailer confirmed that the Sentinels will feature in the 2026 flick, and Doom could even be the one weaponizing the mutant-killing machines, playing right into his history of meshing magic and technology.
On this X-Men-centric Earth, Ian McKellen's Magneto will reportedly be "finally ruling Genosha" and have completed his mutant utopia. Here, he will supposedly have his own "royal family," including Variants of Wanda and Pietro Maximoff, as well as his other daughter, Polaris.
McKellen slipped up and spoiled one part of his Doomsday role in an interview with Jake's Takes, saying that he "did destroy New Jersey the other day." It's unclear whether this will take place in the X-Men's world, Earth-616, or another.
At 86 years old, the Lord of the Rings star will become the oldest main actor in MCU history, and yet, Magneto has still been proclaimed the MVP of Doomsday.
Avengers: Doomsday's Secret Heroes
Marvel Studios announced most of the cast of Avengers: Doomsday in February 2025 before production and has since added a few more names. While it seems those who were part of that chair-centric event were Avengers 5's main cast members, at least most of them, there are still some major players being kept secret.
MTTSH revealed that some of the younger heroes will come to play in Doomsday, including Iman Vellani's Kamala Khan, Hailee Steinfeld's Kate Bishop, and Kathryn Newton's Cassie Lang, setting up the MCU's future Champions.
That scoop included more unannounced names, such as Ryan Reynolds' Deadpool, Hugh Jackman's Wolverine, Gwyneth Paltrow's Pepper Potts, and Owen Wilson's Mobius, although the extent of their roles is unclear.
It has previously been stated that Avengers 5 will feature "multiple Doctor Dooms," but it appears that these won't be Multiversal Variants (ala Kang), rather followers who assist him in Doomsday and perhaps Secret Wars.
MTTSH revealed that at least two of these magical followers will be played by familiar MCU superstars, Benedict Cumberbatch and Hayley Atwell.
Fans already learned of seven X-Men who the Avengers will encounter and fight on this Earth, and it's possible even more familiar mutants will appear.
Loki's MacGuffin Role
One of Avengers: Doomsday's biggest heroes whose role remains a mystery is Tom Hiddleston's Loki, who is returning after his Disney+ series with an important part to play as the God of Stories, holding the Multiverse's branches together.
Disney may have hinted that Loki will actually become an Avenger in Doomsday, reuniting him with his brother, Chris Hemsworth's Thor, and taking him full circle from being the team's first adversary in 2012's Battle of New York.
But there may be more to Loki's part than just that, as scooper Alex Perez described the God of Stories' role as Doomsday's "MacGuffin." The movie is said to be a "race" to reach Loki, with Doom presumably looking to steal his power.
Doom's Pre-Secret Wars Victory
Just as Avengers: Infinity War climaxed with Thanos' Snap, RDJ's Doom will presumably leave Doomsday victorious, setting up Secret Wars. Sam Wilson actor Anthony Mackie already spoiled that Avengers 5 ends on a cliffhanger that fans will be waiting a full year to see resolved on December 17, 2027.
A key element of 2015's Secret Wars in Marvel Comics is that it takes place on Battleworld, a patchwork reality created and ruled over by God Emperor Doom from the remnants of the Multiverse after the final Incursion.
It's easy to imagine Doom seizing Loki's control over the Multiverse (replacing the role of the Beyonders in the comics) to create Battleworld as the credits roll.
It should be noted that none of this seems to explain why Doom has the same face as Tony Stark, or why his sidekicks look like Doctor Strange and Peggy Carter. But that explanation may not come in Avengers 5 at all, as, according to John Campea, the answers to that mystery will be saved for Secret Wars.
There are bound to be more pit stops along the way in Doomsday, as the picture is much clearer for the first half of the movie than the rest. Notably, the Avengers blockbuster will reportedly revisit the Void from Loki and Deadpool & Wolverine, but it's tough to see how that or anything TVA-related ties into the plot yet.
