After the cataclysmic events in New York with The Avengers, Steve Rogers, aka Captain America is living quietly in Washington, D.C. and trying to adjust to the modern world. But when a S.H.I.E.L.D. colleague comes under attack, Steve becomes embroiled in a web of intrigue that threatens to put the world at risk. Joining forces with the Black Widow, Captain America struggles to expose the ever-widening conspiracy while fighting off professional assassins sent to silence him at every turn. When the full scope of the villainous plot is revealed, Captain America and the Black Widow enlist the help of a new ally, the Falcon. However, they soon find themselves up against an unexpected and formidable enemy—the Winter Soldier.
渐渐习惯了现代生活的美国队长史蒂夫·罗杰斯(克里斯·埃文斯 Chris Evans 饰),在一次行动后隐隐嗅到神盾局内部所弥漫出来的凶险气味。而当得知神盾局正秘密进行的“洞察计划”后,他更为此感到愤怒。某天,神盾局指挥官尼克-法瑞(塞缪尔·杰克逊 Samuel L. Jackson 饰)遭到一群武装分子袭击,他拼尽全力将一支U盘交到美国队长手中,这里面藏着该局二战以来最重要且最可怕的秘密。在此之后,美国队长因涉嫌杀害尼克而遭到前局长亚历山大·皮尔斯(罗伯特·雷德福/Robert Redford 饰)的通缉和追杀,逃亡中他得到黑寡妇(斯嘉丽·约翰逊 Scarlett Johansson 饰)和退伍老兵“猎鹰”(安东尼·麦凯 Anthony Mackie 饰)的帮助。
他们必须争分夺秒解开神盾局的秘密,阻止“洞察计划”的施行……