MCU Book Revealed in 2021 That Marvel Wanted Robert Downey Jr. for Doctor Doom Before

The biggest news to come out of San Diego Comic Con this weekend was the revelation that Robert Downey, Jr. would return to play Victor Von Doom, the big bad behind Avengers: Doomsday and Avengers: Secret Wars. Those two films, which will be shot soon and will land in theaters in May of 2026 and 2027 respectively, will bring together the casts of Captain America: Brave New World, Thunderbolts*, and Fantastic Four: First Steps to face off against Doom. It isn’t immediately clear which other Marvel stars will and won’t return, but it wouldn’t be surprising to see some of that news start to take shape in the coming months.

Apparently, though, this is not the first time Marvel has considered Downey as a possible Doctor Doom. In their 2021 book The Story of Marvel Studios: The Making of the Marvel Cinematic Universe, authors Tara Bennett and Paul Terry quoted Jon Favreau as saying as much. Reflecting his meeting with Downey, the Iron Man director revealed that Marvel had already put the two in a room once before…

“Marvel had already had me in a room with him [before], I think, to play Doctor Doom,” Favreau recalled. “I was a little startruck, because I grew up watching him.”

Bennett shared a scan from that section of the book to Instagram over the weekend, with the quote circled and the news of Downey’s MCU return. You can see that below.

Without more context, the likely scenario seems to be that Downey was considered for a role in 2005’s Fantastic Four, before the part ultimately went to Charmed and Nip/Tuck star Julian McMahon. That movie, which starred future MCU Captain America Chris Evans, was a hit, but its sequel failed to spark with the audience and the franchise disappeared for almost a decade.

With almost everyone assuming Secret Wars would be loosely adapted from the Jonathan Hickman comic of the same title (as opposed to the 1980s version, which was more like a Mortal Kombat-type story), there had been speculation for years that Doom would prove to be the ultimate villain of the sixth Avengers movie. There had also been speculation that Downey might return to make a cameo as a variant of Iron Man — but we not too many predicting the two would be intertwined.

The Downey-as-Doom announcement really sucked up a lot of oxygen over the weekend, leaving all corners of the geek internet talking about the MCU again. We’ll see how much of that momentum can carry through to the release of Captain America: Brave New World and Thunderbolts* next year, but between the huge box office Deadpool & Wolverine is soaking up and the hype from San Diego, it’s easy to feel more bullish about the studio’s future than we were a year ago.

Avengers: Doomsday will hit theaters in May, 2026.