This is the third “Captain America” film.

    After a brief prologue* set in 1991, the film dives into action overkill* on the streets of Lagos, where the Avengers chase down a group of murderous mercenaries*. The heroes defeat the criminals, but not before the energy-projecting Wanda “Scarlet Witch” Maximoff (Elizabeth Olsen) inadvertently* sets a high-rise on fire, causing many deaths.

    The variously “enhanced individuals” who make up the Avengers have been operating as an independent group, no longer under the protection of the spy agency SHIELD, and the nations of the world have taken notice of their damage. The U.S. secretary of state (William Hurt) warns them that the United Nations is about to ratify* the Sokovia Accords, named after a fictional country that figured in “Avengers: Age of Ultron,” and where things didn’t go so well for the citizens. The agreement would put the group under the supervision of a U.N. panel, and the superheroics of anyone who doesn’t sign on will no longer be approved.

    Stark (Robert Downey Jr.), shaken by a confrontation* with the mother of someone killed in Sokovia (Alfre Woodard), is ready to be “put in check.” But Rogers (Chris Evans), who is a frozen and revivified member of the Greatest Generation, still in his youthful prime, sees giving in to the demands as giving up. And so the lines are drawn, with charmer Sam “The Falcon” Wilson (Anthony Mackie) the first to join Team Cap. Natasha “Black Widow” Romanoff (Scarlett Johansson), War Machine (Don Cheadle) and the nonhuman, purple-visaged Vision (Paul Bettany) side with Iron Man, which soon puts them in the position of policing their former colleagues.

    There’s the complicating matter of a cruel villain, Zemo (Daniel Bruhl), and the race to stop him. And, not least, there’s the necessity of world-colliding skirmishes* between Team Cap and Team Iron Man.

    Matters of friendship, family and loyalty course through the action.

    (SD-Agencies)