Welcome back RDJ, we've been waiting a long time now!
Ironman switches bodies with Doctor Doom. The storyline that will see RDJ's return makes sense #drdoom
Robert Downey Jr. is back! No, he's not coming back as some Tony Stark variant popping in from the multiverse. Instead, he will be seen playing the villain, Doctor Doom instead. The actor will return to the Marvel Cinematic Universe in Avengers 5 which has now been officially renamed Avengers: Doomsday. Well, the MCU's Kang days are officially over.
And while we're all very happy to have RDJ back, we're really a little confused. Since the supes are pretty well versed in who Tony Stark was, Doctor Doom's resemblance to him in appearance might be a bit problematic. However, all of this can be overcome if Marvel decides to adapt the plot into a series – what if? Iron Man: Demon in an Armor.
What if? Iron Man: Demon in an Armor was published in 2010 and was written by David Michelinie & Bob Layton. In the comic, Tony Stark and Victor Von Doom were roomies in college and of course something had to go wrong.