David Harbour has quickly become an MCU mainstay, racking up appearances in Black Widow, What If...?, and Thunderbolts*. As a member of the New Avengers—or should that be New Avengerz?—he'll return as Red Guardian in Avengers: Doomsday.
At the very least, fans will want to see Alexei Shostakov finally meet Captain America, something that's looking increasingly likely amid reports that Chris Evans will return as Steve Rogers.
Talking to Screen Rant at Rose City Comic Con, Harbour reflected on his experience shooting Avengers: Doomsday, comparing it to the quality and scale of Marvel Studios event movies like Captain America: Civil War and Avengers: Infinity War.
"I was not even convinced when we started, and this movie's gonna be really good. They have a special sauce," the actor teased. "I don't even really understand, but they [the Russos] just know how to do these things."
"I think that, as evidenced in Civil War, as evidenced in Infinity War, there's something about the layers in which they put the comedy and the drama and the surprises and the scale and the epicness and all that stuff. It's incredible," Harbour continued. "I will say I've never been on a set like this in my life. I've never seen anything like this."
"You saw those chairs. So it's like, every one of those guys and girls has a trailer. It's just insane to look around the room and be like, 'Oh my god, I'm in the movie. There's what's his face doing that speech.' It's just enormous," he added.
It's hard to imagine Red Guardian having the biggest role in Avengers: Doomsday, and the post-credits scene for Thunderbolts* indicated that the movie will utilise him in a comedic capacity.
The Russo Brothers have laid the groundwork for there being a conflict between the New Avengers and Sam Wilson's Avengers teams, so that's likely to also come into play next December.
Avengers: Doomsday stars Chris Hemsworth, Anthony Mackie, Winston Duke, Tom Hiddleston, Sebastian Stan, Letitia Wright, Paul Rudd, and Robert Downey Jr. Wyatt Russell, Simu Liu, Tenoch Huerta Mejia, Florence Pugh, Danny Ramirez, David Harbour, Hannah John-Kamen, and Lewis Pullman all make their Avengers franchise debuts in the movie.
The Fantastic Four: First Steps leads Pedro Pascal, Vanessa Kirby, Ebon Moss-Bachrach, and Joseph Quinn join them, as do X-Men franchise stars Kelsey Grammer, Patrick Stewart, Ian McKellen, Alan Cumming, Rebecca Romijn, James Marsden, and Deadpool & Wolverine star Channing Tatum.
Chris Evans, Hayley Atwell, and Ryan Reynolds are also set to appear, according to recent reports from the trades.
The Russo Brothers direct the movie from a screenplay by Stephen McFeely, with whom they previously collaborated on the Avengers and Captain America franchises. Loki and Doctor Strange in the Multiverse of Madness's Michael Waldron is also working on the script.
Avengers: Doomsday is set to be released on December 18, 2026, with Avengers: Secret Wars scheduled to arrive on December 17, 2027.