D.C. and works for the espionage agency S.H.I.E.L.D. while adjusting to contemporary society. Rogers, along with the agency’s S.T.R.I.K.E. team and agent Natasha Romanoff, is sent to free hostages aboard a S.H.I.E.L.D. vessel from pirates led by mercenary Georges Batroc. Mid-mission, Rogers discovers Romanoff has another agenda: to extract data from the ship’s computers for S.H.I.E.L.D. director Nick Fury. Rogers returns to the Triskelion, S.H.I.E.L.D.’s headquarters, to confront Fury and is briefed about Operation Insight: three Helicarriers linked to spy satellites, designed to preemptively eliminate threats. Fury, unable to decrypt Romanoff’s recovered data, becomes suspicious about Insight.
On his way to rendezvous with Maria Hill, Fury is ambushed by assailants led by a mysterious assassin called the Winter Soldier. Fury escapes to Rogers’s apartment, and warns him that S.H.I.E.L.D. is compromised. After handing Rogers a flash drive containing data from the ship, Fury is gunned down by the Winter Soldier. Fury dies in surgery, and Hill recovers the body. The next day, senior S.H.I.E.L.D. official Alexander Pierce summons Rogers to the Triskelion. When Rogers withholds Fury’s information, Pierce brands him a fugitive. Hunted by the agency, Rogers meets with Romanoff. Using data in the flash drive they discover a secret S.H.I.E.L.D. bunker in New Jersey, where they activate a supercomputer containing the preserved consciousness of Arnim Zola. Zola reveals that since S.H.I.E.L.D. was founded after World War II, HYDRA has secretly operated within its ranks, sowing global chaos in the hope that humanity would willingly surrender its freedom in exchange for security. The pair narrowly escape death when a S.H.I.E.L.D. missile destroys the bunker.
Rogers and Romanoff enlist the help of Sam Wilson, a former military pararescueman whom Rogers befriended, and acquire his powered “Falcon” wingpack. Deducing S.H.I.E.L.D. agent Jasper Sitwell is a HYDRA mole, they force him to divulge that Zola developed a data-mining algorithm that can identify individuals who might become future threats to HYDRA’s plans. The Insight Helicarriers will sweep the globe, using satellite-guided guns to eliminate these individuals. En route to S.H.I.E.L.D. headquarters, Rogers, Romanoff, and Wilson are ambushed by the Winter Soldier and Sitwell is thrown into oncoming traffic. During the fight, Rogers recognizes the Winter Soldier as Bucky Barnes, his World War II comrade, before being captured by S.H.I.E.L.D. Hill rescues them and leads them to a safehouse where Fury, who had faked his death, is waiting with plans to sabotage the Helicarriers by replacing their controller chips.
After members of the World Security Council arrive for the Helicarriers’ launch, Rogers reveals HYDRA’s plot to everyone at the Triskelion. Romanoff, disguised as one of the Council members, disarms Pierce. Fury arrives and forces Pierce to unlock access to S.H.I.E.L.D’s database so Romanoff can expose HYDRA by leaking classified information. After a struggle, Fury shoots Pierce dead. Meanwhile, Rogers and Wilson storm two Helicarriers and replace the controllers, but the Winter Soldier destroys Wilson’s suit and fights Rogers on the third. Rogers fends him off and replaces the final chip, allowing Hill to take control and have the vessels shoot down each other. Rogers falls from the Helicarrier as it crashes into the Triskelion, where Wilson fights HYDRA infiltrator Rumlow, the S.T.R.I.K.E. team’s leader. Rogers lands in the Potomac River and is rescued by the Winter Soldier, who then disappears. With S.H.I.E.L.D. in disarray, Fury, under the cover of his apparent death, heads to Eastern Europe in pursuit of HYDRA’s remaining cells as Romanoff appears before a Senate subcommittee. Rogers and Wilson decide to track down the Winter Soldier with information from Romanoff on the Winter Soldier program.
In a mid-credits scene, Baron von Strucker, at a HYDRA lab, proclaims the “age of miracles” has begun as scientists examine an energy-filled scepter and two prisoners: one with superhuman speed, the other with telekinetic powers. In a post-credits scene, the Winter Soldier visits a Captain America exhibit at the Smithsonian Institution.