‘Avengers: Doomsday’ Theory Suggests the Real Doom Is Hiding in Plain Sight

After Marvel Studios released a new trailer for Avengers: Doomsday at D23, a surprising fan theory emerged that the movie will feature two Doctor Dooms. One would be an ally played by Robert Downey Jr., while the truly evil Doctor Doom will make himself known later in the movie. We’ve already broken down that rumor and why it is highly unlikely, but that hasn’t stopped some fans from forming wild theories about whom this supposed second Doctor Doom could be.

Based on one brief trailer shot of Doctor Doom’s eyes, some have concluded that Academy Award winner and Robert Downey Jr.’s Oppenheimer co-star Cillian Murphy is truly under the mask and will be the MCU’s true Doctor Doom. The questions of how or why Marvel Studios would keep that casting secret or pay Robert Downey Jr. $100 million for such a ruse pretty much debunk the theory. Yet even if, by the quantum realm, microscopic chance Murphy was Doctor Doom, that still poses the same problem as casting Robert Downey Jr. as Doctor Doom.

Marvel Fans Think Cillian Murphy Is Doctor Doom – He Probably Isn’t

Right up front, we can say with 99% certainty that Cillian Murphy is not playing Doctor Doom. For that to be the case, you’d have to believe the movie has two Doctor Dooms, which nothing in the movie’s marketing suggests. The specific eye shot that fans are speculating about, showing Doom having blue eyes and therefore must be Murphy, is flimsy at best, as many actors have blue eyes. But the assumption is wrong: the eyes are green; the scene lighting just makes them look blue. Robert Downey Jr., who has brown eyes, is wearing contacts to play Doctor Doom to begin with.

The other is that Murphy’s supposed role as Doctor Doom comes from nowhere. While Murphy was a popular fan pick for Doctor Doom before Downey Jr. landed the part, no credible source links Murphy to ever meeting with Marvel Studios for any role, let alone Doctor Doom. The only link is a 2023 interview in which he said he would accept the part depending on “the script.” Even though some might cite Sadie Sink’s recent reveal as Jean Grey as Marvel holding out for a surprise on opening night, Sink was still known to be part of the cast of Spider-Man: Brand New Day for over a year.

At the end of the day, the fan theory feels like wishful thinking from a segment of the audience who are still upset with the decision to cast Robert Downey Jr. as Doctor Doom. While casting Murphy might square the minor headcanon issue of why Tony Stark and Doctor Doom have the same face (though it isn’t that deep, as Deadpool & Wolverine reminded everyone Chris Evans played Captain America and The Human Torch), it still has the same problem as Downey’s initial casting. Neither actor is of Romani heritage.

Casting Cillian Murphy Wouldn’t Fix the Whitewashing of Doctor Doom

When Robert Downey Jr. was first cast as Doctor Doom, there was a lot of criticism. Some of it was typical fandom issues, like not grasping the in-universe logic or doubting that a talented actor can do a part that dates back to the outcry over Michael Keaton as Batman. However, there was legitimate criticism of Downey Jr.’s casting: the fact that Downey Jr. is not of Romani origin.

In Marvel Comics, Victor von Doom is one of the most prominent Romani characters, and his heritage is key to his origin. Casting Downey Jr. as Doctor Doom was whitewashing the character. Marvel Studios could have found an actor of Romani descent. The studio has had great luck finding unknown talent, like Iman Vellani for Ms. Marvel and, more recently, Maya Boyd as Storm. Yet they instead decided to prioritize a big-name star who is a great actor, mind you, to play the iconic role rather than stay true to the character’s comic book heritage.

So casting Cillian Murphy as the “real” Doctor Doom does not solve the whitewashing criticism. It is the same problem, as Murphy is also not of Romani descent; he is of Irish descent. If Cillian Murphy were revealed as Doctor Doom in Avengers: Doomsday, that wouldn’t fix the one major problem with Downey Jr.’s casting. It just replaces one great actor with another, while spending millions of dollars and ignoring the initial problem.

Release Date

December 18, 2026

Runtime

165 Minutes