For those who have looked back in anger and awe to the Magical Mystery Tour of the '60s, "Beatlemania" is a vindication and an evocation of all that was bright, brittle and painful about those crowded years.

"Beatlemania," which opened a six-week engagement at the Warner Theater last night, is theantithesis of Sha Na Na nostalgia. The advertisements called it "an incredible simulation," but the punch the show packs is to play-acting as 14-carat gold is to gold lame jumpsuits.

The show has two interwoven themes: the music of the Beatles as as it reflected and reformed the society of the '60s; and the '60s themselves, limned in slide, storbe, film and videotape.

From the assassination of President Kennedy to the pastoral placidness of Woodstock, "Beatlemania" careens across the just-past and the near present. Demonstrators march barefoot to Selma; Nixon bows farewell to the press; Chicago police club unarmed protesters in the streets; Martin Luther King and Robert Kennedy foresee a promised land; bomb craters litter Vietnam.

Although at times symbolism is unavoidably heavy-handed as such shows must and should be, there are wrenching moments of recognition, as when a Cambodian Buddhist blossoms in the fiery petals of self-immolation.

As to the music itself, it is almost stunning in its compression. In the space of five or six years, the Beatles transformed popular music to a degree not equaled since.

The Beatles of this show are not merely symbols of a type, as Sha Na Na spoofs a genre of slickedback shoo-wop; they are studies in the being and evolution of a frighteningly influential social force.

Tony Kishman as Paul McCartney, Bobby Wirth as John Lennon, Jimmy Poe as George Harrison and Sy Goraieb as Ringo Starr have studied and memorized every movement, note and mis-note from 29 Lennon-McCartney compositions. Kishman and Poe are dead ringers, Wirth and Goraieb less striking but still familiar. The only thing wrong with the picture is that Kishman is right handed; McCartney played southpaw.

However, let it be noted that before being cast, Kishman had never played bass or piano and Poe had never played lead guitar. Their performance, indeed their expertise, is extraordinary.

The best moments include Kishman's "Long and Winding Road," the melancholic "Eleanor Rigby" and the paralyzingly brutal "Helter Skelter," set against the technicolor images of protest and riot.

Visually the illusion is strongest in the opening segments, with a clean-cut, identically suited Beatles looking as if they just stepped off the tape after Ed Sullivan's introduction. After that the effect varies -- John looks better, George looks worse.

There's a cheerful irreverence toward chronology in the music. "Come Together" is followed by "With a Little Help from My Friends"; "Magical Mystery Tour" is followed by "Lucy in the Sky with Diamonds." But it does begin with "I Want to Hold Your Hand" and end, almost religiously, with "Let It Be."

The most engaging quality about these Beatles is the natural charm which marked their models. Looking back, the mothers who saw them as sweet next-door boys were quite right, and not even their later, more strident proselytizing blunted that charm.

The audience is an essential part of the performance, and last night's crowd warmly accommodated by clapping, cheering and yelling requests.

The music is live, performed entirely by the four "Beatles" and five backstage musicians who provide the strings, reeds, mellotron, etc.All live, that, is, except for the three minutes or so of "Can't Buy Me Love," which is on tape to allow for the most elaborate of the cast's nine costume changes. The sound is extraordinary, and mixed far better than was probably ever possible at a real Beatles appearance. It's the best of both worlds -- perfectly mixed music and warm bodies.

In the orchestra sat Chip Carter and sister Amy, flanked by Secret Service men. The Carters were whisked away just before the ending to an upstairs dressing room where they were to be photographed with the Beatlemaniacs (as the actors are regrettably but inevitably known).

On the average last night's fans were too young to have seen the Beatles on stage, but they were intimately familiar with the details of each song. They were similarly moved by the images of the past which levitated about them. Nixon was booed, RFK cheered, King met with respectful silence. There were a few good-natured cat calls as nude Woodstockians appeared projected on the several screens, but they were muted by the palpable wave of pride and identification which swept the crowd.

Fifteen years ago this month, when the Beatles made their American TV debut on the Ed Sullivan show, the critics sneered and swore that "Beatlemania" wouldn't last out the year. There is something, therefore, not only moving but reassuring and exhilarating about the success of "Beatlemania." Those of us who put our faith in the Beatles and in the '60s were not deceived.