Jonathan Majors Hints at MCU Return: Could Robert Downey Jr. as Doctor Doom Take Down Kang in Secret Wars?

Marvel rumor season is doing what it does best: stirring the pot. Jonathan Majors is back in the headlines, Doctor Doom chatter is getting louder, and there is a very loud theory about how Marvel might pivot from Kang to something bigger. Let’s break it down without getting lost in the noise.

Jonathan Majors, Kang, and the carefully worded non-answer

Majors was asked by The Sun about talk that he might return as Kang the Conqueror in an upcoming Marvel movie. He didn’t confirm anything, but he didn’t shut it down either.

"I cannot say anything about that. Well it’s a multi-verse, so there’s always that. Always a lot of opportunity for that."

Quick reminder of the timeline: Marvel fired Majors in December 2023 after a New York City jury found him guilty of misdemeanor assault and harassment in a domestic violence case involving his ex-girlfriend, Grace Jabbari. Since then, he’s dealt with major public fallout and career turbulence. Whether you’re ready for it or not, he’s clearly hoping for a comeback, and the multiverse is the easiest narrative tool for Marvel to use if they want to thread that needle.

From Kang to Doom: the big villain pivot (allegedly)

There’s a steady drumbeat that Marvel has shifted focus away from Kang as the ultimate big bad and toward Doctor Doom. The story making the rounds says the title Avengers: The Kang Dynasty quietly became Avengers: Doomsday, and that Marvel leadership started talking Doom as the long-game villain even before Majors’ legal trouble.

Paraphrasing what Kevin Feige reportedly told The Hollywood Reporter: Marvel had begun realizing that Kang wasn’t on the Thanos level, and the one character who could fill that decades-long comic-book stature was Doctor Doom. Thanks to the Fox acquisition, Doom was finally on the board, and conversations about pivoting started before the studio officially moved away from Kang.

The 'Worf Effect' and why Doom might stomp someone early

There’s a tried-and-true storytelling move where you establish a new villain’s threat level by having them crush someone already established as powerful. Fans call it the Worf Effect. Applied here, the buzzy pitch is simple: open strong by having Doctor Doom annihilate Kang in Avengers: Doomsday. There’s comic-book precedent for Doom erasing top-tier threats in a blink — in Marvel’s Secret Wars, he straight-up kills Thanos in one brutal beat. It’s efficient storytelling and instantly tells the audience, yeah, this guy’s worse.

The wild theory tying it all together

Majors’ coy multiverse tease has poured gas on a particularly bold fan theory: Robert Downey Jr. shows up not as Tony Stark, but as Doctor Doom, and Doom kills Kang on sight — a cinematic mic drop that resets the board and announces the new alpha. Is it confirmed? No. Is it the kind of swing Marvel might take to get momentum back? Honestly, could be.

So what is Avengers: Doomsday supposed to be?

Here’s what’s being passed around right now by outlets and rumor traders, with FandomWire among those laying out the specifics. Treat it all as unconfirmed until Marvel says otherwise:

• Title: Avengers: Doomsday
• US release date: December 18, 2026
• MCU phase: Phase Six
• Directors: Anthony Russo and Joe Russo
• Writers: Michael Waldron and Stephen McFeely
• Composer: Alan Silvestri
• Filming: April 2025 to September 2025
• Locations: England and Bahrain
• Premise: Set 14 months after Thunderbolts* (2025). The Avengers team up with Wakanda, the Fantastic Four, a new roster of Avengers, and the original X-Men to face Doctor Doom.
• Doom’s goal: Collapse the multiverse (which would keep Kang relevant to the plot whether or not Majors returns).
• Sequel: Leads into Avengers: Secret Wars
• Status: Filming reportedly completed; now in post-production

Where this leaves Kang — and Majors

Phase 5 spent time setting up Kang across Ant-Man and the Wasp: Quantumania and Loki, and then the real world crashed through the wall. If Marvel wants a cleaner runway, using Doom as the new apex villain makes sense. If Majors returns for one last bow — even as a multiversal variant — it could give audiences closure and hand Doom an immediate statement win. If he doesn’t, the multiverse still lets Marvel resolve the Kang thread without him.

Bottom line: Majors is playing coy, Doom talk is getting louder, and December 18, 2026 is the date to circle if Avengers: Doomsday is really what’s coming. Multiverse rules mean pretty much anything is possible — which is either the beauty of it or the headache, depending on your patience level.

Where are you on a possible Majors return — curious, cautious, or hard pass?