Of all the characters in Thunderbolts*, Bucky (Sebastian Stan) is the one with the most extensive MCU history. He first appeared as Steve Rogers’ (Chris Evans) best friend in 2011’s Captain America: The First Avenger, before returning as the villainous Winter Soldier, being saved, and looking for redemption over a decade of movies and TV shows. Recently, Bucky’s journey took an unexpected turn when Captain America: Brave New World revealed he was running for Congress, willing to use his experience as a politician. Thunderbolts* keeps Bucky’s story unfolding, as he has to face the benefits and limitations of working within the system.
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WARNING: Spoilers below for Thunderbolts*
When Thunderbolts* kicks off, Bucky has been elected congressman by the people of Brooklyn. He’s not too comfortable in this position, as he struggles to put together meaningful speeches to the press and obviously would prefer to take more direct action against injustice than spend time reading lengthy documents and preparing for public audiences. Still, Bucky is making a genuine effort to overcome his vigilante days as a way to atone for the sins of his past.
As a congressman, Bucky is particularly interested in the impeachment process of CIA director Valentina Allegra de Fontaine (Julia Louis-Dreyfus). Through the shady company OXE, Valentina has been setting up illegal laboratories in poor countries and overseeing human experiments to create a superhero she can control. Unfortunately, Congress has a hard time proving it, as Valentina is smart enough to burn all evidence that could connect her to these heinous crimes.

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Trying to do his part to take Valentina down, Bucky approaches Mel (Geraldine Viswanathan), Valentina’s assistant. He knows Mel is troubled about Valentina’s methodology and wants her to give away information that can send the CIA director to prison. At first, Mel resists, but as Valentina becomes more unhinged, she reaches out to Bucky for help. While Bucky would prefer to deal with everything above board, his only opportunity to defeat Valentina is to track Mel down and intercept one of her operations as the Winter Soldier.
Bucky’s return to the vigilante field puts him on a collision course with Yelena (Florence Pugh) and the other operatives Valentina tried to kill to protect her secrets. Once he learns about Project Sentry and how dangerous Bob (Lewis Pullman) can be, Bucky sees no option but to join the Thunderbolts and help them rescue the poor man from Valentina’s clutches. He uses his bloody past to inspire the others, explaining how everyone has a shot at redemption, and even assassins can become heroes if they choose to. Just like that, Bucky embraces his Winter Soldier persona once more, taking a step away from politics. The shift is fully complete by the end of Thunderbolts*, when Bucky becomes a key member of the New Avengers team.
Bucky Will Be on the Frontlines of Avengers: Doomsday

By the end of Thunderbolts*, Bucky helps Yelena and the others to subdue the Void by giving Bob the emotional support he so desperately needs. Once the world-ending threat is dealt with, Bucky decides it’s time to apprehend Valentina and make her pay for her crimes. Before that happens, Valentina tricks the Thunderbolts into a press conference where the CIA director quickly introduces them as the New Avengers, telling the world she is behind the new generation of world defenders. Knowing how important it is for the others to get a clean slate and the opportunity to officially become heroes, Bucky goes with the flow.
The post-credits scene of Thunderbolts* reveals Bucky has been working as a member of the New Avengers for 14 months. The team still struggles with public perception, as not everyone believes in second chances. However, the U.S. government sanctioned the New Avengers, giving them the authority to pursue their heroic dreams. As arguably the most powerful member of the New Avengers, since Bob has abandoned his Sentry persona to keep the Void in check, Bucky will be a key fighter when Doctor Doom comes to the Sacred Timeline.
Since in the post-credits scene the New Avengers become aware of the Fantastic Four’s ship coming to Earth from a different dimension, Bucky and his new teammates will also be on the frontlines of Avengers: Doomsday. His importance extends beyond the battlefield, though. The post-credits scene also reveals Sam Wilson (Anthony Mackie) is forming his own Avengers team and has been very vocal against the New Avengers. As Sam’s close friend and a former ally to both Captain Americas, Bucky can help the two teams to put their differences aside and work together for the greater good, when the time comes.
Thunderbolts* is now available in theaters. Avengers: Doomsday is scheduled for release on May 1, 2026, followed by Avengers: Secret Wars on May 7, 2027.
Are you excited about Bucky’s return in Avengers: Doomsday? Let us know in the comments!