Everything to Know About Robert Downey Jr.'s Return to the MCU

From Avenger to antagonist! Robert Downey Jr. is returning to the Marvel Cinematic Universe with a new role. While he played a hero in the Infinity Saga, the Avengers star is set to appear as an iconic villain in the Multiverse Saga—making him the living embodiment of the quote, "You either die a hero, or you live long enough to see yourself become the villain"...though in Downey's case, he's doing both.

"New mask, same task," the Oscar winner said at Marvel Studios’ Hall H showcase at San Diego Comic-Con 2024 after it was revealed that he will be portraying Victor von Doom in the next Avengers movie.

“What can I tell you? I like playing complicated characters," Downey added.

Here is everything we know about Robert Downey Jr.'s surprise return to the MCU, plus how fellow Marvel stars reacted to the big news...

How is it possible for Robert Downey Jr. to play another Marvel character?

Downey is coming back not as Tony Stark, who died in Avengers: Endgame, but instead as a character who has not yet been introduced in the MCU: Victor von Doom. Before unveiling the Iron Man actor as the "one person who could play" Dr. Doom, director Joe Russo said it was "proof of the unimaginable possibilities in the Marvel Multi-Universe."

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Who is directing Avengers: Doomsday?

The Russo Brothers, Anthony and Joe Russo, are returning to helm Avengers: Doomsday, as well as Avengers: Secret Wars. The two previously directed Avengers: Endgame, Avengers: Infinity War, Captain America: Civil War and Captain America: Winter Solider.

"Being able to create stories and explore characters within the Marvel Universe fulfilled a life-long dream of ours, and we discovered a powerful connection with audiences in each film that we made," the Russo Brothers said in a statement. "We’re thrilled to collaborate once again with Kevin, Lou and the entire Marvel team to bring this epic adventure in storytelling to new and surprising places for both the fans and ourselves."

When will Avengers: Doomsday premiere?

Avengers: Doomsday is slated for May 2026, followed by Avengers: Secret Wars in 2027.

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How do I watch Avengers: Doomsday and Avengers: Secret Wars?

The Marvel flicks will be released only in theaters.

Who is in the cast of Avengers: Doomsday?

In addition to Downey, Marvel Studios producer and president Kevin Feige confirmed at San Diego Comic-Con 2024 that the cast of The Fantastic Four: First Steps movie—starring Pedro Pascal (Reed Richards/Mr. Fantastic), Vanessa Kirby (Sue Storm/The Invisible Woman), Joseph Quinn (Johnny Storm/The Human Torch) and Ebon Moss-Bachrach (Ben Grimm/Thing)—will appear in the next two Avengers movies.

Jeremy Renner, who plays Clint Barton/Hawkeye in the MCU, had fans speculating as to whether he'd be appearing in the film after sharing the title treatments for both Avengers: Doomsday and Avengers: Secret Wars on his Instagram Story.

What will happen in Avengers: Doomsday?

A logline for movie has not yet been revealed, but director Anthony Russo explained at San Diego Comic-Con 2024 that they needed to make "another essential movie first"—aka Avengers: Doomsday—"in order for all of us to be ready for Secret Wars." Joe noted that Dr. Doom is “one very, very important character that is required to do Secret Wars justice."

How Marvel stars reacted to Robert Downey Jr.'s return to the MCU:

Naturally the news of Downey's big return sparked reactions from other Marvel stars. Gwyneth Paltrow, who played Tony Stark's love interest Pepper Potts, commented on the actor's Instagram announcement: "I don’t get it, are you a baddie now?" Meanwhile, Downey's fellow Avenger Jeremy Renner penned: "Bringing the DOOM ??!!!" Over on X (formerly Twitter) Avengers star Mark Ruffalo, wrote: "Hey Brat, green suits you."

Thunderbolts* actress Florence Pugh's jaw dropped as she watched a video of the reveal. "I bet it went insane in there!" she told Variety at Comic-Con.

David Harbour called it "bad news" for the Thunderbolts. Speaking to Variety about Downey, Harbour said, "That guy’s, according to the Russo Brothers, the greatest actor in the world. Nobody wants to act with that guy."

Thunderbolts* actor Lewis Pullman described Downey's return as "amazing." "I mean, that's a beautiful thing because he was, in many ways, the origin of this whole universe," he told GamesRadar+. "That's awesome. Love to hear that."

Sebastian Stan, who plays Bucky Barnes in the MCU, revealed to Variety that he found out about Downey at San Diego Comic-Con. He shared, "Listen, as soon as I got out of the car after five hours of driving over here, someone said, 'Robert is here.' And I was like, 'That’s not happening, that’s not happening.' I think we just found out on the spot."

Stan also pointed out: "There’s absolutely nothing that Robert Downey Jr. can’t do," adding, "For me, it feels like something's right in the world again with seeing him up there, so I think it's exciting."

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