There are so many things going right in "X-Men: First Class" that you can almost overlook its glaring faults. A richly layered, intelligently worked-out prequel, it melds a dozen back stories, globe-hopping thrills and historic political confrontations, yet it never packs too many sardines into the tin.

The film has a mature confidence rarely seen in comic-book fare, with powerful drama and throwaway wit in perfect balance.

The film gives a fresh start to the X-Men story line, with its mutant heroes alienated from human society. Director/co-writer Matthew Vaughn introduces his parallel protagonists with swift, sure strokes.

In a World War II prologue, young Erik Lehnsherr, who will become Magneto, discovers his telekinetic powers at the hands of a sadistic Nazi scientist. Half a world away, Charles Xavier, the future Professor X, is raised amid wealth and comfort, using his telepathic gifts to calm and help an outcast girl.

The seeds of the characters planted, the tale skips ahead two decades. Erik uses his powers to hunt down the Nazis who killed his parents, executing them without remorse. "I'm Frankenstein's monster, looking for my creator," he tells one fugitive war criminal before dispatching him. Charles, a young college lecturer, turns his empathic skills to advantage in his extracurricular womanizing. Neither is a clear-cut villain or hero, and when they meet, their differences are simply philosophical disagreements between close friends.

The duo are recruited by the CIA to locate others of their kind who can help combat Soviet aggression. As they gradually encounter younger peers, Charles envisions a world where mutants and humans peacefully coexist. Erik sees humans as persecutors and mutants as the next step in evolutionary progress. Their true natures are tested by a power-mad mutant bent on inflaming U.S.-Russian tensions into a nuclear holocaust. The film races ahead like a thoroughbred thriller, with every action sequence logically motivated by the story.

The tale is ideally served by returning to the early 1960s. The film's production design has a sleek retro allure; the look of the U.S. war room is a direct nod to "Dr. Strangelove," and the costumes are slim-cut, hip and sexy, if slightly anachronistic (miniskirts and men with long hair were still years away). Setting the action at the dawn of the civil rights movement and feminism gives the story social and political significance that's relevant even now. When one closeted mutant on the CIA payroll clarifies why he has kept his powers secret, he explains, "They didn't ask, I didn't tell."

A film so dependent on character dynamics needs fine actors in its lead roles. James McAvoy is superb as Charles, playing the patient, good-humored idealist with delicacy. Michael Fassbender is coolly charismatic, rueful and lethal as Erik. The actors are both in their early 30s, but McAvoy still carries some baby fat in his cheeks, while Fassbender has a lean, wolfish look. Over the course of the film they round up five teen mutants, who are thinly characterized, and the shape-shifting Raven (Jennifer Lawrence), who appears to be a blond, blue-eyed angel because she uses her camouflage abilities to hide her natural appearance.

The biggest problem with the film is the nemesis. Kevin Bacon plays Dr. Schmidt, the concentration-camp physician who unlocks Erik's rage, and thus his magnetic abilities. From the moment he appears onscreen, speaking ill-accented German, Bacon strikes a false note. He's equally unconvincing in the 1960s chapter of the film, reincarnated as a lounge lizard Bond baddie named Sebastian Shaw. Dressed in mod splendor and swilling cocktails, his performance drips oily excess. He's also saddled with an illogical and unexplained transformation. Somehow he has acquired mutant powers of his own, which punctures the crucial plot point that humans and mutants are on separate evolutionary tracks.

Still, the four-way faceoff between heroic and evil mutants and the U.S. and U.S.S.R. during the missile blockade is as taut and thrilling a showdown as we've seen in months. In almost every important regard, the new "X-Men" is first-class indeed.

Colin Covert • 612-673-7186