Could Robert Downey Jr. Play Both Dr. Doom and Iron Man? Our Theories

The auditorium shook at San Diego Comic-Con this past weekend when a costumed Doctor Doom unmasked himself, only to reveal Robert Downey Jr. The actor, known for his iconic portrayal of Iron Man, marked his return to the Marvel Cinematic Universe (MCU). After Tony Stark sacrificed himself at the end of Avengers: Endgame, Downey Jr. is set to save the MCU again. The biggest question now is, “How?!”

Marvel clearly has a plan to reintroduce Downey Jr. As the actor told Esquire earlier this year, “Never, ever bet against Kevin Feige. It is a losing bet. He’s the house. He will always win.” Whatever Feige, Marvel’s mastermind, has crafted for Downey Jr. has enticed him enough to return. Now, he will pivot from Marvel’s greatest hero to its greatest villain. “What can I tell ya?” Downey Jr. shared with the Comic-Con crowd. “I like playing complicated characters.”

Reintroducing Downey Jr.’s character poses a challenging task for Marvel. They have the expansive multiverse at their disposal—a sandbox of endless possibilities—but is the next big adversary that straightforward? Let’s explore some theories about Downey Jr.’s return.

He’s An Evil Tony Stark from Another Universe

The multiverse provides an easy solution: our Tony Stark is dead, but another Tony Stark could exist in an alternate universe. This variant could turn evil and use his mechanical genius to become Doom instead of Iron Man. Perhaps he went mad after failing to stop Thanos, or maybe he never fell in love. This alternate Stark theory is currently popular.

The comics provide some precedent. In Marvel Team-Up (2004), Robert Kirkman wrote about an alternate-universe Tony Stark who becomes Doctor Doom. In this story, the Stark variant hails from a war-torn planet where an alien named Titannus kills most of the Avengers. Angry at Reed Richards for failing to stop the villain, Stark dons Doom’s armor and attempts to destroy our universe’s Fantastic Four.

Doom Becomes Iron Man After Stark’s Death

In Infamous Iron Man (2016) by Brian Michael Bendis, Doom takes up the mantle of Iron Man following Stark’s death. This happens after a second Civil War event (though Stark eventually returns). Doom creates an Iron Man suit that resembles his Doom outfit and tries to become a force for good.

While this story is popular, it’s complicated to execute. Not only does Doom become a hero in Infamous Iron Man, but he doesn’t resemble Tony Stark. This connection between Stark and Doom is intriguing but may not clarify Downey’s return.

Doom takes up the mantle of Iron Man after Stark dies in 2016’s Infamous Iron Man.

Iron Man and Kang Have a Loose Connection

In Young Avengers (2005) by Allan Heinberg, a variant of Kang the Conqueror wears Iron Man armor. This could facilitate a transition from Jonathan Majors (Kang) to Downey Jr. (Doom). Majors was dismissed after his arrest for reckless assault and harassment, right when he was expected to become the next significant villain. Making Doom a Kang variant could ease the transition, but Young Avengers is an intricate story.

Named Iron Lad, the young hero from the future is an adolescent Kang variant. Seeking to avoid a villainous future, he travels back in time to form the Young Avengers. Though he wears an Iron Man-like suit, his character doesn’t explain why he would resemble Tony Stark.

A variant of Kang that wears armor like Iron Man’s named Iron Lad could bridge the two movies for the MCU.

Maybe He’s A New Person Entirely

This might be the laziest approach Marvel could take, but simply claiming that the person who looks like Tony Stark is someone entirely different is still possible. While this decision may not satisfy fans, it remains a possibility. As highlighted above, figuring out how Doom is also Tony Stark is a formidable task. By the time we see Avengers: Doomsday on May 1, 2026, let’s hope Marvel does not disappoint.

Source: Various Sources