The movie opens in 1991, with a frozen Winter Soldier (Sebastian Stan) being thawed out for another in a series of murderous missions. (Marvel fans will recall that he is Bucky Barnes, Captain America’s wartime—that is to say, WW II-time—best friend, who was long ago given a bionic arm and brainwashed into becoming an assassin for the international conspiracy Hydra.) One after another, the code words needed to activate the killer are spoken: “daybreak … furnace … homecoming … freight car …”
Flash forward to present-day Lagos, where an Avengers squad made up of Captain America (Chris Evans), Black Widow (Scarlett Johansson), Falcon (Anthony Mackie), and Scarlet Witch (Elizabeth Olsen) is foiling the theft of a biological weapon. (Blink for a moment, and you’ll miss a brief appearance by Brock Rumlow, a.k.a. Crossbones, as the head thief.) Civilians are injured in the process, however, which leads to the requisite handwringing back at Avengers HQ. “People died,” explains Cap. “It’s on me.”
The litany of accumulating havoc is quickly itemized: New York (The Avengers), Washington, D.C. (Winter Soldier), the fictional Eastern European nation of Sokovia (Age of Ultron), and now Lagos—everywhere the Avengers seek to do good, they wind up leaving a trail of destruction. Given this record, the U.S. Secretary of State, Thaddeus Ross (William Hurt, and yes, he does appear to be this Thaddeus Ross), proposes that the Avengers submit to United Nations oversight.
Cap immediately balks at the idea, having learned firsthand in Winter Soldier that taking orders from a global security entity can turn out rather badly. But somewhat more surprisingly, Tony Stark (a.k.a. Iron Man, a.k.a. Robert Downey Jr.) thinks that this submission to a higher authority is a good idea. So does his pal James “Rhodey” Rhodes (a.k.a. War Machine, a.k.a. Don Cheadle)—though his comment, “This is the United Nations we’re talking about,” suggests he’s not terribly familiar with the organization’s overall record of efficacy. (Do you really want Vladimir Putin to have veto authority over the Avengers?)
And so the lines are drawn: Stark, Rhodey, Black Widow, and the Vision (Paul Bettany) on the side of UN oversight; and Cap, Falcon, and Scarlet Witch against. The former group will eventually add a Wakandan prince in Black Panther (Chadwick Boseman) and a Queens teenager in Spider-Man (Tom Holland); the latter group will bring in Hawkeye (Jeremy Renner), Cap’s pal Bucky—by now wanted by law enforcement for a new act of Winter Soldier terrorism—and Ant-Man (Paul Rudd). Need a scorecard yet? If not, you surely will by the time the movie introduces additional characters played by Daniel Brühl, Alfre Woodard, Martin Freeman, Hope Davis, and Marisa Tomei (who may be the least spinster-y version of Peter Parker’s Aunt May ever committed to screen).