Robert Downey Jr. is 'immersed' in creating Doctor Doom, Russo Bros. say

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Robert Downey Jr. is deep in preparation mode for his return to the Marvel Cinematic Universe.

Directors Joe and Anthony Russo tell Entertainment Tonight that the former Iron Man actor, who’ll be playing the villain Doctor Doom in the upcoming Avengers: Doomsday, is in the “very intense process” of developing the character.

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“He is so immersed in it. He is so dialed in,” Joe Russo said. “He’s writing backstory, costume ideas … We were just on the phone with him this morning before we got here talking about it. He just loves really rich three-dimensional characters. He sees a real opportunity here with the character.”

Downey’s surprise casting was announced at Comic-Con last year. He previously played Iron Man in 10 films, before being killed off in 2019’s Avengers: Endgame.

Avengers: Doomsday also marks the Russo brothers’ return to the franchise after helming Endgame. They’ll also direct Doomsday’s follow-up, Avengers: Secret Wars. Doomsday is currently set for a May 2026 release.

Marvel Studios is owned by Disney, the parent company of ABC News.