Phase Zero
Characters

Bucky Barnes

The Winter Soldier

James Buchanan BarnesCaptain AmericaEarth-616

The best friend who was already a soldier when Steve Rogers was still being turned away at recruiting offices, and who spent seventy years being used as a weapon by the people who caught him.

Bucky Barnes is the only person in this story whose entire arc is about not being responsible for what he did. Everything Hydra used him for happened; the question the films keep circling is whether any of it was him.

He starts as the confident one. In 1943 he is a sergeant with a unit and a future, and Steve Rogers is a small man being told no by every recruiter in New York. Their positions reverse, and then keep reversing. The fall from the train should have killed him. The serum he was given without asking is why it did not.

What follows is seventy years as an instrument: tortured, wiped, kept frozen between assignments, brought out when Hydra needed somebody dead. When the films finally give him his memory back, they do not give him relief with it. They give him the list.

Show detailsThe trigger words

The programming is not portrayed as a mood or a corruption. It is a phrase, and anybody holding the book it is written in can read it aloud and take the man out of his own body.

Helmut Zemo does exactly that in Captain America: Civil War, in a room, with a piece of paper, and it is the most frightening thing anyone does in that film precisely because it takes no power at all.

Played by
Sebastian Stan
Role
Sergeant, assassin, and eventually a congressman
Born
10 March 1917
Affiliation
Howling Commandos, formerly Hydra, Avengers, United States Army
What they can do
A super soldier serum he did not volunteer for, and an arm that is not his.

The journey

What happens to this person, title by title.

  1. Captain America: The First Avenger2011

    Drafted while his friend is still being rejected, he fights across Europe with the Howling Commandos and falls from a train.

  2. Captain America: The Winter Soldier2014

    He comes back as Hydra's asset, with no memory of who he was, and spends most of the film trying to kill the only person who recognises him.

  3. Captain America: Civil War2016

    Living quietly in Bucharest, he is framed for the Vienna bombing, and Helmut Zemo proves he can still be switched on with a sentence.

  4. Black Panther2018

    A farm in Wakanda, and the first time anyone has offered to take the programming out rather than use it.

  5. Avengers: Infinity War2018

    A new vibranium arm, a battlefield full of people he barely knows, and a place in a line he chose to stand in.

  6. Captain America: Brave New World2025

    A pardon, a life in Brooklyn, and a therapist he does not tell the truth to.

Appears in

  1. Captain America: The First Avenger2011
  2. Captain America: The Winter Soldier2014
  3. Ant-Man2015
  4. Captain America: Civil War2016
  5. Black Panther2018
  6. Avengers: Infinity War2018
  7. Avengers: Endgame2019
  8. Captain America: Brave New World2025
  9. Thunderbolts*2025

Sources

Facts last checked on Sep 7, 2026