Guardians of the Galaxy trilogy director and DC Studios CEO James Gunn shares his thoughts on Robert Downey Jr.’s MCU return as Doctor Doom in Avengers: Doomsday. Robert Downey Jr. bid farewell to Iron Man in Avengers: Endgame, where Tony Stark sacrificed his life to defeat Thanos. However, Marvel Studios is bringing Downey Jr. back in the Multiverse Saga, not as a new Iron Man variant, but as the MCU’s next big bad — Doctor Doom, who will be Kang the Conqueror’s replacement as the main antagonist in the Russo Bros.’ Avengers: Doomsday and Avengers: Secret Wars, released in 2026 and 2027, respectively.

Speaking to Josh Horowitz in an episode of Happy Sad Confused, James Gunn praises Marvel Studios’ decision to cast Robert Downey Jr. as the MCU’s Doctor Doom, saying “I thought it was a smart move, I was excited about it. And I also love Robert, so it’s… I think that’s cool. I think it’s… I think it’s a great idea, and I think that… you know, there’s no better than him.” Gunn also reveals that he’s “totally okay” with whatever the MCU does with the Guardians of the Galaxy, saying that Marvel has his blessing to move in new directions with the characters. Watch Gunn’s full interview below:

Robert Downey Jr.’s Casting As Doctor Doom Was Always Going To Be A Win For Marvel

Robert Downey Jr.’s Doctor Doom casting announcement was undeniably the biggest highlight at San Diego Comic-Con 2024, as Downey Jr.’s MCU retirement was though to be definitive, or at least much longer. Seeing the MCU’s biggest star return at the end of the Multiverse Saga, regardless of the plot, is an automatic pull for audiences. How RDJ’s Doctor Doom will differ from Iron Man, where the villain comes from, and what Doom’s interactions with the Avengers will look like are questions that will inevitably bring audiences to theaters when Avengers: Doomsday arrives.

Related Robert Downey Jr.’s MCU Return MUST Include This Reversal of His Very First Iron Man Scene Robert Downey Jr.’s very first scene in 2008’s Iron Man can be perfectly repurposed to introduce him as Doctor Doom, and Marvel already proved it.

From a business perspective, Robert Downey Jr.’s MCU return is indeed “a smart move”, as James Gunn describes it. Doctor Doom’s introduction in Avengers: Doomsday offers Downey Jr. the chance to show off his acting chops in a brand-new role, and it also avoids undoing Iron Man’s perfect MCU story in the process. Besides, the Multiverse Saga may provide reasonable explanations for this decision due to the concept of alternate timelines.

Robert Downey Jr.’s Doctor Doom Needs To Live Up To The Hype
Custom image by Nicolas Ayala

While Robert Downey Jr.’s return as Doctor Doom is enough to attract a huge crowd, Marvel Studios needs to justify the RDJ’s villain casting in Avengers: Doomsday. MCU villains like Loki and Thanos have left the bar really high for MCU antagonists, and Doctor Doom is one of the most important villains in comic book history. If RDJ’s Doctor Doom fails to meet expectations, the actor’s return could backfire, as it could be seen as a last resort to raise interest in Avengers: Doomsday after Marvel Studios scrapped its plans for Kang the Conqueror.

Source: Happy Sad Confused

Release Date May 1, 2026 Main Genre Superhero

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