THUNDERBOLTS* Star Confirms Return For AVENGERS: DOOMSDAY Reshoots: “[The Movie] Is Massive”

Avengers: Doomsday reshoots are scheduled for April (possibly March), and Black Widow and Thunderbolts* star David Harbour has now confirmed that he’ll be part of them.

The Stranger Things star is expected to have a sizeable role in the movie as Red Guardian, especially as he’s a member of the New Avengers. It’s also previously been reported that Alexi Shostakov will develop a friendship with Ben Grimm, a.k.a. The Thing.

Rumour has it, Avengers: Doomsday may have started shooting without a finished script. However, after filming wrapped last September, Marvel Studios and the Russo Brothers have had plenty of time to refine the story and figure out the best way to bridge the gap to 2027’s Avengers: Secret Wars.

Talking in the video below, Harbour says, “I’ve been working a lot. Keeping busy. And this little Avengers movie that we got in London. They got a couple more days they want to do. I’m heading there soon [and] actually going to London for a couple of days. There’s a little more filming coming up for ‘Avengers: Doomsday.'”

“I’m really excited about it. The chemistry with Sebastian [Stan] and Wyatt [Russell] on set was fantastic, so I’m looking forward to getting back in there,” the actor continued, adding with a laugh, “You know I can’t say anything. But it’s gonna be fun. The Russos are killing it, and the whole thing is shaping up to be massive.”

It’s not exactly a spoiler that Red Guardian will be spending time with Bucky Barnes and U.S. Agent, seeing as they’re part of the same superhero team. Thunderbolts* struggled at the box office, though that’s unlikely to impact plans for the New Avengers in Avengers: Doomsday.

The movie is expected to feature many casualties, which are inevitable as the Final Incursion beckons. Will Alexi be among those who fall in battle against Doctor Doom? That remains to be seen. 

You can hear more from Harbour in the player below.

David Harbour reveals he’s about to do more “Avengers: Doomsday” filming, talks new “genre-defying” series “DTF St. Louis.” pic.twitter.com/srp3fAJKPm

— ExtraTV (@extratv) February 25, 2026

Avengers: Doomsday officially stars Chris Evans, 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, Mabel Cadena, Florence Pugh, Danny Ramirez, David Harbour, Hannah John-Kamen, Lewis Pullman, and India Rose Hemsworth all make their Avengers franchise debuts.

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, with Deadpool & Wolverine star Channing Tatum. The trades have pointed to Ryan Reynolds and Hayley Atwell also appearing in Avengers: Doomsday.

The Russo Brothers direct Avengers: Doomsday and Avengers: Secret Wars 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 has also been enlisted to help.

Avengers: Doomsday is set to be released on December 18, with Avengers: Secret Wars scheduled to arrive on December 17, 2027.