Overview

In 1991, super-soldier James "Bucky" Barnes is sent on a mission by Hydra to intercept a case of super-soldier serum in Siberia. In the present day, after the Avengers thwart Brock Rumlow's attempt to steal a biological weapon in Lagos, a division emerges among them. U.S. Secretary of State Thaddeus Ross proposes the Sokovia Accords, leading to disagreement between Tony Stark, who supports oversight, and Steve Rogers, who values his judgment.

Meanwhile, Helmut Zemo eliminates Barnes' Hydra handler and acquires trigger words to control him. A bombing at a UN conference in Vienna leads to accusations against Barnes, and T'Challa of Wakanda seeks revenge for his father's death. Rogers decides to apprehend Barnes to protect him, leading to a confrontation in Bucharest with T'Challa and the authorities. Zemo manipulates Barnes and reveals his involvement in the Vienna bombing.

Rogers and Wilson recruit Maximoff, Barton, and Lang without authorization. Stark forms a team with Romanoff, T'Challa, Rhodes, Vision, and Peter Parker to capture Rogers' team. A battle at Leipzig/Halle Airport ensues, with Romanoff ultimately joining Rogers and Barnes. Vision accidentally paralyzes Rhodes, and Rogers' team is imprisoned, while Romanoff goes into exile.

Stark learns of Zemo's plot and seeks Rogers and Barnes' help. They discover Zemo's actions and that Barnes was forced to kill Stark's parents. Stark turns against them and now the friends start to fight each other.