December 20, 1991 | Oliver Stone’s JFK is a brilliantly manipulative melodrama, a masterpiece of historical revisionism writ large and urgent in tabloid style. Whether you should believe a word of it is open to debate. But there can be no denying the mesmerizing skill of Stone's storytelling technique, or the sheer adrenaline rush that it provides for anyone willing to risk the wild ride.

In a way, JFK is a deeply troubling film, and not just because it lends credence to the worst suspicions of the most paranoid conspiracy buffs. JFK illustrates how easily -- and how compellingly -- a world-class moviemaker can blend documented fact, informed speculation and wild rumor into a seamless whole, to manufacture a fiction with the solid and persuasive ring of truth.

Stone has made no secret of his willingness to alter facts in his search for a higher truth in such films as Born on the Fourth of July or The Doors. Here, however, he goes several steps further, mixing documentary footage and dramatic re-creations, black-and-white reality with wide-screen invention, heavily footnoted conspiracy theories with shamelessly corny Hollywood conventions. The result is something that looks, sounds and, most important, feels like it can be believed.

Indeed, JFK as a whole is a great deal more convincing than New Orleans District Attorney Jim Garrison actually was when, in the late 1960s, he argued his most famous criminal case. Garrison contended that the Warren Commission got it all wrong, that President John F. Kennedy was not killed by a lone assassin, but rather was murdered as a result of a labyrinthine conspiracy that involved anti-Castro Cubans, CIA operatives, mafia bag men and right-wing homosexuals.

Clay Shaw, a prominent New Orleans businessman, was charged by Garrison as a major force in organizing the plot. A New Orleans jury heard the evidence that Garrison and his assistants gathered -- and then, on March 1, 1969, declared Shaw not guilty. But that jury might not have been so quick to dismiss Garrison's theories if the district attorney had argued his case with as much down-home, salt-of-the-earth fervor that Kevin Costner conveys while portraying Garrison in JFK. The movie, which is based in part on Garrison's book On the Trail of the Assassins, presents a heroic and humane Garrison who appears to have stepped out of some old-fashioned, all-American small-town drama directed by the late Frank Capra.

Costner wears nerdy eyeglasses, adopts a folksy twang and does his best to come off as the soul mate of the impassioned idealist James Stewart played in Capra's Mr. Smith Goes to Washington. Forget about the large, booming and frequently intimidating Jim Garrison of fact -- Stone and Costner give us a kinder, gentler Jim Garrison of legend. It may be bogus, but it's tremendously effective as dramatic license.

Costner's ingratiating underplaying as Garrison provides a much-needed center of gravity for JFK, keeping the film from flying apart as it repeatedly whips itself into hyperventilating frenzies. The movie is slightly more than three hours long, but seems much shorter as it zips forward at warp-speed, cramming an amazing amount of lucid detail and vivid speculation into its rapid-fire montages.

Only when Stone and co-scriptwriter Zachary Sklar go overboard in their efforts to ''humanize'' Garrison, and have the obsessed district attorney squabbling with his neglected wife, is the pace pokey and the dialogue silly. As Mrs. Garrison, Sissy Spacek deserves some sort of award for maintaining a straight face while mouthing such banalities as, ''I think you care more about John Kennedy than your own family!''

Stone has cast many familiar faces in supporting roles, bit parts and brief walk-ons, and that goes a long way toward helping the audience keep track of the teeming cast of witnesses, prosecutors and alleged conspirators. Standouts include Tommy Lee Jones, who plays Clay Shaw with an effete, almost feline self-assurance, and Joe Pesci as the hairless, hot-wired David Ferrie, a defrocked priest turned mercenary pilot whose death damages Garrison's case.

Chief among the other notables: Kevin Bacon as a male prostitute who fingers Shaw as a conspirator; Donald Sutherland as a nameless military official who tells Garrison of high-level duplicity; Michael Rooker and Jay O. Sanders as the district attorney's most prominent investigators; Walter
Matthau as Sen. Russell Long; Gary Oldman as a spooky and spooked-out Lee Harvey Oswald; and Jack Lemmon as a private investigator with secrets he wishes he didn't have to keep. Look closely, and you will see Jim Garrison himself as Supreme Court Chief Justice Earl Warren.

In the world according to JFK, Garrison insists that the murder of John F. Kennedy was an American coup d'etat, ordered by leaders of the military-industrial complex who feared the president was dangerously soft on communism, and willing to wind down U.S. involvement in Vietnam. As he sums up Garrison's assassination theories for the jury, Costner sounds very passionate, very heroic, very convincing. That's part of what makes JFK so gripping as drama - and so disturbing as dramatized history.