A fascinating MCU theory points out that Robert Downey Jr.'s casting as Doctor Doom is likely going to change a key Thanos line from Avengers: Infinity War. Following the Mad Titan as he finally collects all the Infinity Stones, Infinity War includes Thanos' battle to claim the Time Stone which features an epic sequence where he goes head-to-head with Downey Jr.'s Iron Man. This results in one of the Mad Titan's most poignant lines, one that will most likely take on a whole new meaning in Avengers 5.
Custom Image by Kevin Erdmann
As was announced at San Diego Comic-Con 2024, Robert Downey Jr. has been cast as the MCU's Doctor Doom, and will serve as the big bad in Avengers: Doomsday. He'll likely be the big bad in Avengers: Secret Wars as well. Keeping that in mind, one of Thanos' best Infinity War lines to Iron Man will likely take on a whole new meaning now that Downey will be playing Doctor Doom in the MCU.
Robert Downey Jr's Return As Doctor Doom Changes Thanos's "I Hope They Remember You" Line
The Avengers May Have To Reconcile Doom With The Iron Man They Once Knew
While battling Iron Man, Spider-Man, Doctor Strange, and a number of the Guardians of the Galaxy on Titan, there are a few sequences where the Mad Titan gets to fight Iron Man directly. Not only does Thanos confirm that he's long been aware of who Tony Stark is, but he also shares his respect for Iron Man despite Stark's efforts to prevent his erasure of half of life in the universe. As such, this interaction also provides one of Thanos' best lines:
"When I'm done, half of humanity will still be alive. I hope they remember you."
While the line is powerful, it hits even harder following Avengers: Endgame after Iron Man gives his life using the Infinity Gauntlet to defeat Thanos and his forces. However, the argument can be made that the line may soon take on a whole new kind of meaning in light of Robert Downey Jr.'s Doctor Doom casting. After all, one can imagine that several of the Avengers will likely have a hard time reconciling the new villain they'll soon encounter with the hero they remember, especially if he has the same face.