Robert Downey Jr. returns to MCU 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.