And the filmmakers don't beg any indulgence for themselves. True, they never lay out within the film that the Stones had hired them. And they don't touch on the role the movie played in precipitating the concert's last-minute move from Sears Point Raceway in Sonoma to Altamont Speedway. (Among other conditions, Filmways Inc., which controlled Sears Point, wanted the film's distribution rights.)

But by using the structural device of having the Stones witness the footage, the filmmakers break the illusion of seamless omniscience -- an illusion they're skillful enough to maintain if they want to -- and raise the question of their own complicity. Why are they showing this chronicle to the Stones? Are they themselves looking for the Stones' approval -- and our blessing? "Gimme Shelter" is a self-reflexive movie in the best sense: While presenting a chronicle of a catastrophe, it implicitly asks the audience to keep one eye focused on the chroniclers.

As I thought about the movie and interviewed a dozen people who either worked on it or attended the concert, several directed me toward the Jan. 21, 1970, Rolling Stone, which devoted 15 copy-crammed pages to Altamont under the headline, "Let It Bleed." It is often spoken of as the ultimate authority on the event. But when it comes to the widespread misrepresentation of the movie, I discovered, it was more like a smoking gun.

Marcus was at Altamont and with 10 others helped cover it for that issue of Rolling Stone; John Burks edited their contributions, newsweekly style, into one headlong unsigned piece. It's a mammoth and laudable example of on-the-spot journalism, and it helped redefine the concert in the public consciousness as the anti-Woodstock.

The legend of Altamont as apocalypse was largely based on that Rolling Stone cover story. Unfortunately, it contains a dozen short paragraphs on the movie that pin the blame for the disaster on the making of the movie. These paragraphs are pocked with errors, and lamentable in tone as well as content. They read as if they were written by someone who'd never been close to the making of any kind of movie. The magazine's chief movie critic at the time, Michael Goodwin, was at the concert, but his contributions to the piece were limited to a transcription of Jagger's exhortations for the crowd to calm down and "be cool"; Goodwin had recited the words into his tape recorder as Jagger said them, so they wouldn't get lost in the mob noise.

The introductory sentence to the movie section lays down some heavy attitude: "It may surprise many of the people who suffered Altamont to discover that they were, in effect, unpaid extras in a full production color motion picture." A cameraman says David Maysles told him to ignore a large naked woman "freaking out backstage" and shoot only "beautiful things." The whole account portrays the filmmakers as slick hired guns helping the Stones beat "Woodstock" to the screen, using Hells Angels as their bodyguards. Typical sentence: "The Stones figure they spent something like $80,000 on the Altamont affair, including helicopters, which isn't bad at all -- when you consider [it] as the cost of a movie set."

The Rolling Stone attack on the movie became by default the official story -- the one other journalists and fact-checkers would rely on. The "movie set" and "unpaid extras" slams from the Rolling Stone article are echoed, for example, in Kael's statement that "the free concert was staged and lighted to be photographed, and the three hundred thousand people who attended it were the unpaid cast of thousands."

There's one problem: It isn't accurate. Kael's review argued against automatically accepting any film that looks as real as the truth; it's a brilliant and potent critique of the cinéma vérité school of documentary filmmaking in fashion at the time. But even if you embrace her argument, what she had to say about the making of "Gimme Shelter" doesn't fit the Maysles' method. They relied for their effects on molding found material, not spending time and money -- which they didn't have much of at Altamont anyway -- devising a reality "spectacular."

It's understandable that young, rock-oriented moralists looking to explain the disaster would turn moviemakers into villains. And the Maysles and Zwerin may have also misled their critics by putting the film together in a confident and seemingly inevitable way, as if Altamont were always its final destination and Mick Jagger's storm-cloud stare always its endpoint.

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