Tony Stark sacrificed his life to save the universe in Avengers: Endgame. It was arguably the most shocking moment in a movie full of shocking moments. Marvel Cinematic Universe fans are still coming to grips with losing Iron Man a year after the movie premiered in theaters and have thought about all kinds of ways he could come back.

One way is in the upcoming Black Widow movie in the form of a flashback since it takes place before the events of Infinity War. When recently asked about the possibility, Scarlett Johansson smiled and wouldn't talk about it. Now, the Russo Brothers are discussing whether or not Stark could come back to the MCU.

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Even if Tony Stark has a small cameo in Black Widow, which has not been officially confirmed, it would be huge. But what about the future? Can Robert Downey Jr. return to the role in a present-day MCU project? Before looking at that question, the Russo Brothers discussed what made Stark's death so powerful in the first place. Anthony Russo explains.

"I mean look, certainly we've always said this and we believe this about stakes have to be real, and if they're not real, like the audience's emotional investment in the moment and in those characters in the narrative is only... is contingent upon them feeling like there's potential, there's something to be lost."

After Infinity War and before Avengers: Endgame opened in theaters, the Russo Brothers always maintained that the deaths wouldn't be reversed and that they would stick. The characters that were Decimated by Thanos were not dead, but Gamora and Vision certainly were. The same can be said for Tony Stark, Steve Rogers, and Natasha Romanoff at this time. We know how Romanoff is coming back, but MCU fans would be thrilled to see Stark at some point. Anthony Russo had this to say about the possibilities of Stark coming back.

"So in all of our storytelling, even though those Marvel movies a lot of the story was difficult, we wanted to commit very hard to that idea. So to answer your question, I think it would be in the context of that. It depends on how he was brought back. It depends on the storytelling, but it is certainly something that has to be earned. It's certainly something that would shock and surprise audiences, so you can't simply just bring him back. There would have to be a really compelling, innovative, unpredictable narrative event to find your way there in order for it to be worth it."

While MCU fans would love to see, or even just hear, Robert Downey Jr. come back as Tony Stark, most of them know that it would have to be some clever storytelling. Marvel Studios and their team would have to cook up something really good, or it wouldn't work and it would cheapen Avengers: Endgame. Plus, it's unclear if Downey Jr. would even want to return after devoting 11 years of his life to the MCU.

Robert Downey Jr. and Chris Evans decided that they would leave the party before being asked to leave when it came to the MCU. While fans would love to see them both return, Avengers: Endgame was the perfect place to bow out. While they may lend their voices along the way, it appears that their days of getting back into the gym and getting into superhero shape are behind them, at least for now. The interview with the Russo Brothers was originally conducted by Cinemablend.