Marvel writer Deniz Camp hints that The Ultimates #4 will solve the mystery of how Robert Downey Jr. is the MCU’s Doctor Doom

Undoubtedly the biggest story to come out of this year's San Diego Comic Con was the news that Robert Downey Jr. will be returning to the MCU, albeit in a new role: Doctor Doom .

The mystery of how and why Doom will be played by the former Iron Man actor has stirred up much speculation, with some suggesting that this Doom will be a variant of Tony Stark, and others wondering if the forthcoming Avengers: Doomsday movie will draw on Brian Michael Bendis and Alex Maleev's Infamous Iron Man comic, which saw Victor Von Doom step into Tony Stark's metal shoes. Now one of Marvel's key writers has suggested that an answer to the mystery may be forthcoming in The Ultimates #4.

"If you want to understand Robert Downey Jr. as Doom, you MUST read Ultimates 4 on sept 4th. (or whenever it comes out)" writer Deniz Camp tweeted on July 28, leading to many confused, amused, and bemused replies.

Now, it strongly seems like this is simply a case of Camp having a bit of fun on social media here and hyping up his comic, but it is true that Doom is a major player in The Ultimates (although in the world of Earth-6160, the man under the mask is Reed Richards rather than Victor Von Doom) and it sounds, from Marvel's synopsis, like the issue will be delving deeply into his character. Here's what it has to say:

"THE FATE OF THE ULTIMATE FANTASTIC FOUR! Doom's years of torture at the hands of the Maker finally catch up to him in this secret history of the real Reed Richards! And tensions rise among the Ultimates when Doom might be more fixated on re-creating the life he should have had than the life he's got..."

So, is this simply a bit of buzz for the new issue, or a genuine hint at things to come? We'll find out for sure when The Ultimates #4 is published by Marvel Comics on September 4.

Find out more about Victor Von Doom in our list of the best Doctor Doom comics here .