Why didn't Red Guardian show up to fight alongside Earth's Mightiest Heroes in Avengers: EndgameBlack Widow star David Harbour has some ideas.

Harbour spoke to Comicbook about his upcoming Marvel Cinematic Universe debut in next month's Black Widow, which will serve as a prequel for Natasha and explore both her past and her life directly after the events of Captain America: Civil War. So while the movie will introduce new characters to the MCU, like Harbour's Alexei Shostakov, they're all technically old characters in the current timeline of the franchise.

When the outlet asked where Red Guardian is these days and what he was doing when the Avengers were fighting Thanos and his forces, the actor said he and director Cate Shortland had some ideas.

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"I mean the fun thing about this entire thing is that we go back and we build out this structure for something new," Harbour said. "So all this new content with a lot of information about the movies that moves forward with these other projects, the new Phase. And you also get to introduce these new characters. Cate Shortland and I had all kinds of speculations about where Red Guardian is, and what happens to him. There were a lot of fun ideas that we had, but I haven't asked [Kevin] Feige himself. I'll do that later."

While it seems clear that Harbour and Shortland crafted some character details for the future of Red Guardian, and thus potentially revealing that the character survives Black Widow, the mention at the end that nothing has been cleared with Marvel Studios head Kevin Feige says it all. For now, it looks like Red Guardian's place in the timeline is up in the air, though perhaps the events of Black Widow will shine some light on his future. After all, this isn't the first time Harbour has teased the Russian Avengers.

Directed by Cate Shortland, Black Widow stars Scarlett Johansson as Natasha Romanoff/Black Widow, Florence Pugh as Yelena Belova, David Harbour as Alexei Shostakov/Red Guardian, O-T Fagbenle as Mason and Rachel Weisz as Melina Vostokoff. The film arrives in theaters and on Disney+ Premier Access July 9.

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Source: Comicbook via The Direct