Vad som helst som Hydra brukade gåva Bucky med de förmågor han har av Captain America: The Winter Soldier hade redan startats av Dr Arnim Zola när han räddades från sitt laboratorium i den österrikiska Hydra Base genom Rogers i Captain America: The First Avenger och fortsatte efter sin uppenbara död senare i filmen.
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Using S.H.I.E.L.D.'s resources, Zola continued his experiments on Bucky Barnes with other doctors to turn him into HYDRA's secret weapon/assassin. Zola also managed to build an entire computer system which his mind was uploaded into as an artificially intelligent user interface. Though Zola's body died in 1972, his mind continued to live in cyberspace, where he was able to provide easy passage into the agency for HYDRA sleeper agents that either managed to escape justice during the war or were corrupted from within.