Avengers: Doomsday Will 'Completely' Change 1 Thunderbolts Character (Confirmed)

One Thunderbolts* character being revisited in Marvel Studios' Avengers: Doomsday is going to go through some major adjustments in the upcoming MCU team-up epic. The self-named team is already set for a major period of change after being dubbed the New Avengers in the MCU. Still, on an individual level, fans are set to see even more new material moving forward.

U.S. Agent star Wyatt Russell teased the changes his character will experience in 2026's Avengers: Doomsday after his leading role in 2025's Thunderbolts*. Russell is about to make his third appearance in the MCU since joining the franchise in 2021's The Falcon and the Winter Soldier, playing a character who has already been through plenty of action in his tenure.

Speaking with The Hollywood Reporter, Russell addressed how Thunderbolts* featured a different version of his John Walker than what fans initially saw on Disney+. However, he teased that he "will be completely different again" when he returns to the MCU in Avengers: Doomsday:

"The John Walker I played in 'Falcon and the Winter Soldier' in 2020 is completely different version than the guy in 'Thunderbolts*' and I think will be completely different again in 'Avengers: Doomsday.'"

Most recently, Russell's John Walker made his second MCU appearance in Thunderbolts*, working for Valentina Allegra de Fontaine before teaming up with the rest of the film's cast. Fans saw a look back at his wife leaving him and taking their son, but he also stepped up as a hero and proved he could be a valuable member of a team in battle. Next, Russell will join the already massive cast of Avengers: Doomsday, which is set to add even more names to the cast list over the coming months. Bringing together teams of Avengers, X-Men, the Fantastic Four, and more, Marvel's biggest names will join forces in an effort to stop a reign of destruction from Robert Downey Jr.'s Doctor Doom. Avengers: Doomsday is currently being filmed, and it will debut in theaters on December 18, 2026.

What To Expect From Wyatt Russell's U.S. Agent in Avengers: Doomsday

Looking ahead to Doomsday, John Walker (utilizing a still misshapen shield) will be part of the newly-dubbed New Avengers alongside Bucky Barnes, Ava Starr, Alexei Shostakov, Robert Reynolds, and Yelena Belova. Already teased for an interaction with the Fantastic Four at the end of their solo movie (14 months after the events of Thunderbolts*), Doomsday is sure to put Walker in unfamiliar territory yet again.

Due to Doomsday's massive cast, it is still unclear how much screentime or focus will be dedicated to furthering John Walker's story. However, even after dealing with something as terrifying as the Void, this will be Walker's first time encountering characters and dangers that come from outside his own universe.

Teaming up with multiple other super soldiers and the current Captain America, Walker will learn about threats on a scale he has never imagined before in the fight against Doom. Whether this means he will have a better or more level-headed perspective on life as a whole is unclear, but he will have to make sure his priorities are straightened out as he continues working with his new team.

As one of a handful of super soldiers taking center stage in this movie, Walker will only be able to do so much in battle compared to heroes with powers that exceed his own in terms of strength. However, it will take a cohesive team effort to win the expectedly difficult battles ahead, meaning it will be vital for Walker not to cause any potential distractions or issues as he and the other heroes fight to keep humanity intact.