The Doctor Doom Theory That Perfectly Explains Why Robert Downey Jr Was Cast

Why is Robert Downey Jr. returning to the Marvel Cinematic Universe? Tony Stark is given an emotional swansong in "Avengers: Endgame," and bringing him back risks ruining that perfect ending. Of course, Downey Jr. is set to play Victor von Doom in "Avengers: Doomsday," meaning that his Iron Man legacy should remain intact, right? Well, maybe not, as Doom and his Stark could be inextricably linked.

Since the casting news came to light, some people are speculating that Downey Jr. will reprise the role of Iron Man, but not in the way you think. Essentially, the "Doomsday" version of the tech whiz superhero will be Stark from another universe — one who used his scientific gifts for evil and became the villainous Doctor Doom instead of the noble Avenger we all know and love.

This isn't a far-fetched notion, as Robert Kirkman's "Marvel Team-Up" sees Stark become Doom because he has a beef with Fantastic Four leader Reed Richards. Similarly, Brian Michael Bendis' "Infamous Iron Man" involves Doom becoming Iron Man after Stark kicks the bucket. Both characters have a history of impersonating each other, and bringing this idea to the screen could make sense if handled correctly. At the same time, is it possible that Marvel is being naughty?

The idea of Doom being a rogue Iron Man is interesting, but maybe it's less complicated than that. The Multiverse boasts infinite timelines and variations of Marvel's heroes and villains. As such, Robert Downey Jr.'s character could be any version of Doom. Furthermore, some fans believe that this is the franchise's way of pulling a classic bait-and-switch, with this iteration of Doom being a precursor to another dangerous threat down the line.

One theory, put forward by Redditor u/Chous18, notes that "Avengers: Doomsday" and "Avengers: Secret Wars" are the Earth's Mightiest Heroes' next big team-up adventures. Given that Jim Shooter, Mike Beck, and Bob Layton's "Secret Wars" comic series is all about variants and the Multiverse, it's likely that Downey Jr.'s Doom will be a variant. However, the Redditor believes that the Sacred Timeline's version of Doom will be revealed in "Secret Wars," allowing Downey Jr.'s stand-in to ride off into the sunset.

That's certainly an interesting theory, and it doesn't seem implausible. That said, "Avengers: Doomsday" could also introduce Doom as a heroic figure who must save the Sacred Timeline from extinction.

In order to explain another theory for why Tony Stark and Doctor Doom are one and the same, we must turn our attention to "Deadpool & Wolverine" and the concept of anchor beings. In that movie, Mr. Paradox (Matthew Macfayden) explains that an anchor being is someone who's so connected to their respective timeline that their death causes their universe to decay. Tony Stark is one of several characters who might be the Sacred Timeline's anchor being, and his demise in "Avengers: Endgame" could have marked the beginning of the end.

As documented by YouTuber Fantasy Theory, it's possible that Stark will be confirmed as the anchor being, and his death has caused Earth-616 to enter apocalyptic mode. To make things right, the Avengers will pluck a new Stark from an alternate timeline, only for him to turn into Doom later on. The "Secret Wars" comics see Earth's Mightiest Heroes recruit a corrupted Iron Man variant who ultimately helps them save the day. Could the upcoming movies be a twist on that idea, or is it too similar to the events of "Loki" Season 2?

Multiversal madness has given Marvel free reign to do anything, so there are countless ways to justify Downey Jr. as Doom. Of course, it remains to be seen if he'll even be one of the bad guys when the Avengers' upcoming adventures are all said and done. Or maybe, just maybe, Doom will keep his mask on and we'll forget that Downey Jr. is behind it, allowing the actor to embody a character that isn't reliant on the complexities the Multiverse.