Marvel has cast Robert Downey Jr. as Doctor Doom in two new Avengers movies

The Marvel Cinematic Universe received a much-needed boost this weekend with the box office dominance of Deadpool and Wolverine, which raked in a record-breaking $438.3 million worldwide and $205 million domestically. And the Marvel panel at this weekend’s San Diego Comic-Con kept up the momentum, delighting attendees with sneak peeks of what’s to come—most notably the return of Robert Downey Jr. to the MCU. The twist: RDJ won’t be donning his usual Iron Man suit. Instead, he’ll be playing Doctor Doom for Avengers: Doomsday (2026), with the Russo brothers returning to direct. This will be followed by the Russo-directed Avengers: Secret Wars (2027).

Comic-Con attendees were also treated to exclusive new footage from Captain America: Brave New World, and updates on Thunderbolts and The Fantastic Four reboot, titled First Steps, as well as a surprise screening of Deadpool and Wolverine.

“New mask, same task”

It’s no secret that Marvel Studios originally planned to build its Phase Six Avengers arc (The Kang Dynasty) around Jonathan Majors’ Kang the Conqueror (and associated Variants), introduced in Loki and last year’s Ant-Man and the Wasp: Quantumania. But then Majors was convicted of “reckless assault and harassment” (domestic violence), and Marvel fired the actor soon after. That meant the studio needed to retool its Phase Six plans, culminating in the announced return of the Russo brothers, who directed four of the MCU’s most successful films, which brought in more than $6 billion at the global box office.

Joe Russo told the assembled fans that he and his brother had thoroughly enjoyed their “incredible” four-movie run, but “it left us with our emotions spent.” But over time, “We came to see a road forward with you all,” Anthony Russo chimed in.

Rather than keeping Kang as the villain and recasting the character, the Russo brothers decided to strike out in a new direction: bringing the Secret Wars storyline to the big screen. It’s one of their favorites and an ambitious task, but before they can take on Avengers: Secret Wars (slated for May 2027), the duo told the audience in Hall H that they had to make another movie first: Avengers: Doomsday (slated for May 2026), featuring the wildly popular comics villain Doctor Doom. Of course, the biggest reveal came when a masked figure dressed in the Doctor’s trademark green came onstage and revealed himself to be none other than RDJ, to wild cheers.

Captain America: Brave New World

Marvel dropped a teaser for Captain America: Brave New World earlier this month, the fifth film in the MCU’s Phase Five, starring Anthony Mackie as the new Captain America and directed by Julius Onah (The Cloverfield Paradox). The film builds on events not just in The Falcon and the Winter Soldier but also in the 2008 film The Incredible Hulk and gives us a tantalizing glimpse of Red Hulk, the superpowered alter ego of President Thaddeus Ross, now played by Harrison Ford. Per the official premise, “Sam finds himself in the middle of an international incident. He must discover the reason behind a nefarious global plot before the true mastermind has the entire world seeing red.”

Carl Lumbley plays Isaiah Bradley, reprising his F&WS role as a Korean War veteran who had been secretly imprisoned and given the Super Soldier Serum against his will, enduring 30 years of experimentation. Rosa Salazar plays Rachel Leighton, Danny Ramirez plays Joaquin Torres, and Shira Haas plays Ruth Bat-Seraph. That earlier teaser also gave us a glimpse of Giancarlo Esposito, and we finally know who he’ll be playing. He emerged on stage Saturday night and announced, “I am Sidewinder!” In the comics, Sidewinder is the alter ego of economics professor Seth Voelker, who gains the power of teleportation via a cloak (a gift from the Egyptian god Set) and forms a criminal organization called The Serpent Society.

Attendees were also treated to an exclusive clip focused on a White House event held by Ross introducing a stockpile of adamantium, the result of a “celestial mass” emerging in the Indian Ocean and now the most valuable element on the planet. “It’s in a secure location and we have our own Captain America to thank for that,” Ross concluded. The footage also featured a better look at Ross turning into Red Hulk and Ross telling Mackie’s Captain America that he wants his help rebuilding the Avengers.

Thunderbolts and Fantastic Four: First Steps

Phase Five will conclude with Thunderbolts, a follow-up of sorts to 2021’s Black Widow. It’s directed by Jake Schreier and stars Wyatt Russell (US Agent/failed Captain America from F&WS), Julia Louis-Dreyfus (Contessa Valentina Allegra), Florence Pugh (Yelena Belova), Sebastian Stan (Bucky Barnes/Winter Soldier), David Harbour (Alexei/Red Guardian), Geraldine Viswanathan, Lewis Pullman, and Olga Kurylenko. It’s described as “an irreverent team-up featuring depressed assassin Yelena Belova alongside the MCU’s least anticipated band of misfits.”