Avengers directors Joe and Anthony Russo are keeping schtum about the plot circumstances surrounding Robert Downey Jr's Doctor Doom role, but they have teased a one-of-a-kind performance from the one-time Iron Man actor.

Doomsday concept poster blends the death of Iron Man in the MCU with the debut of the franchise's version of Doctor Doom.

Anthony Russo was recently asked how they will explain RDJ’s return and his answer was well, mysterious: “We can’t explain that as it’s part of the story,” he said with