From the very first MCUfilm all the way toAvengers: Endgame, Robert Downey Jr.’s Tony Stark has, in many ways, been the backbone of the Marvel films as audiences know them. Whether it was being approached for the Avengers initiative at the end ofIron Manor laying the groundwork for the future of the series with hisSpider-Manconnections, there are few actors who can claim to be as important to the whole experiment as RDJ himself.

Coming in a pretty close second, however, is Chris Evans as Captain America. Even though both characters closed their character arcs at the finale ofEndgame, both will clearly have a heavy presence in the universe that goes beyond their lifespan. Between Iron Man’s continuing influence as a mentor to Tom Holland’s Spider-Man and Captain America’s legacy forming a central storypoint inThe Falcon and The Winter Soldier, the MCU is still quick to remind audiences of what’s been left behind.

Ironheart Iron Man Tony Stark

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So much so, in fact, that many fans are still clamoring fora return of Evans' Captain Americain some form or another. Some have been quick to point out that, despite his age, Captain America has not been confirmed as dead, and even if he was, that doesn’t mean the actor couldn’t return as another MCU character.

As for Evans' thoughts on the matter, he doesn’t seem to think it’ll happen, in part because the role he’d want is already taken. During an interview with ACE Universe, when asked what kind of role he’d want to take in the MCU besides Captain America, he responded he wanted to be Tony Stark: “I mean, I’ll say Downey, Iron Man. The paychecks would be nice, but just the role is so fun.” The fact that role is already taken would be an obvious obstacle, however, and Evans was quick to acknowledge that.

In fact, the actor went so far as to say that trying to playIron Man after Downey Jr.’s runwould be “signing up for failure,” and that no one could improve on what he’s done with the character. As Evans continued, it became clear that he views RDJ as the definitive live-action Iron Man: “I don’t consider that a role that’s gonna be like a James Bond or a Superman or Batman, that somehow other people get a bite at the apple. He’s Iron Man, the end.”

Bold words, but not undeserved. RDJ as Tony Stark is widely considered one of the best casting choicesin a franchise renowned for fantastic casting, and it’s clear that the other stars of the MCU agree. It seems unlikely that anyone else can, or will, step into that Iron Man suit for a long, long time.