If the Kremlin had commissioned a film as part of the Soviet Union's de-Stalinization process, or if the current leaders of China issued a cinematic condemnation of the "Gang of Four," it is easy to imagine to the kind of heavy-handed, vitriolic production that each would be.

"The Private Files of J. Edgar Hoover" is of the same genre.

This is the de-Hooverization film. It portrays the late director of the Federal Bureau of Investigation in about the same way the Russians would treat Joseph Stalin and the Chinese would handle Mao Tse-Tung's widow, Chiang Ch'ing , and her cohorts - and with approximately the same degree of subtlely and artistic sophistication. It is no documentary, as the title might imply, but rather an arch dramatization that combines selective use of recent revelations with flights-of-fancy to depict Hoover as one of the great villains of the century.

For those who grew up on a steady diet of the movies and radio programs that created the FBI's myth of purity and invincibility, or who still watch reruns of the "FBI" television series starring Elrem Zimbalist Jr., as the ideal agent, this will certainly represent a change of pace. To Wit:

Whereas most prior dramatizations of the FBI's work, made with the Bureau's assistance and control, only rarely included violent scenes, this film is packed with gratuitous violence, perpetrated both against and by the G-men.

J. Edgar Hoover, invariably present on the screen as a flawless hero and selfless civil servant in the past, emerges here as a pretty tyrant, and evil genius, a man whose nasty whims took him into battle with presidents and other politicians - and weird and insecure to boot.

FBI agents, long presented as iron men who could and would go no wrong, are now drawn with a thick brush as weak characters - philanderers, wiretappers and burglars - whom one would never want to trust.

To be sure, a certain measure of correction of the FBI's superman image is useful and necessary. And that is what has been happening - even since before Hoover's death in 1972 - in a chain of press reports, congressional investigations and works of fiction and non-fiction.

But it is possible to take that process too far, and to create a kind of laughable revisionist history along the way. That is exactly what has been done in "The Private Files." For unsuspecting moviegoers, the laughter may reach its peak in a scene where an agent, shot down in the street by a pursesnatcher who has just vitimized his wife, uses his dying breaths to worry that "Mr. Hoover's gonna be embarrassed." Or in a scene - possibly one of the tackiest in the history of American film - where the star, Broderick Crawford, playing the aging, perverted Hoover, closets himself in a conference room and gets his kicks by listening to a tape of an illicitly recorded bedroom scene. As the sweat pours down Crawford's face and the background music builds to an overdramatic crescendo, the film loses its last vestiges of credibility.

It fails the credibility test in other ways, too.One need not be an FBI buff to notice that in the film Robert Kennedy is left in the attorney general's job much longer than he actually held it, or that the wave of hijackings that plagued the United States starts up somewhat ahead of schedule. But aficionados will also be disappointed to discover that:

The head of an FBI office is called a "sack" by one of his agents. The term SAC (special-agent-in-charge) is never pronounced that way except by outsiders; an SAC, in the Bureal, is always called an S-A-C.

Hoover is shown meeting personallywith the late Senator Joseph McCarthy to give him secret material from the files for his investigations of alleged Communists. The director was smarter than that; he always funneled the files to McCarthy through someone else, usually one of this key aides in the Bureau, so that he could feign ignorance of the senator's sources.

The Director is seen having a confrontation with President Lyndon Johnson over whether he should retire. Johnson never directly raised the subject with Hoover, but had intermediaries do so; it was Richard Nixon who actually tried (but failed) to persuade him to retire.

Clyde Tolson, Hoover's longtime sidekick, is portrayed as being sharp and fully functioning at the time of Hoover's death, enough so to participate personally in the shredding of the director's secret files. Actually, Tolson was already an invalid before Hoover died, and the files were destroyed by others.

Hoover is found dead in his pajamas. In fact, he never wore pajamas and his chauffeur discovered him nude and unconscious on his bedroom floor.

In some of the nastiest scenes of the movie, one defects the long arm of William C. Sullivan, the one-time Hoover aide who developed many of the FBI's dirty tricks against Communists and other leftists, but was locked out of his office and forced to retire by the director in 1971. Until he died in a hunting accident in New Hampshire last month. Sullivan spent most of his time in his last years trying to destroy Hoover's reputation and serving as a reliable source of anti-Hoover anecdotes for the press. He would have been pleased by this film, which tells many of the old Bureau stories the way he remembered them. (Publicists for the movie have made it clear that producer-director-writer Larry Cohen and his "technical adviser," John Crewdson of The New York Times, spent time with Sullivan while working on "The Private Files.")

The film will probably entertain some of J. Edgar Hoover's most unrelenting detractors; but its long-range importance, if it has any, will be as example of how even in the United States the arts often swing with the political pendulum.

For all the decades when Hoover and his bureau were riding high, the movie and broadcast industries, as well as press, were willing accomplices in an extraordinary propaganda campaign. In Hollywood, productions such as "The House on 92nd St", "Walk a Crooked Mile," and "Walk East on Beacon," the FBI stood as the heroic defender against the espionage threat to the United States. n "The FBI in Peace and War" and "This is Your FBI", radio networks took cases that had been preselected by the Bureau for their glamorization potential and fed them to the public like pabulum. "I Led Three Lives" made a small-time FBI-inspired infiltrator of the American inspired infiltrator or the American Communist Party, Richard Philbrick, into the hero of a hokey television series. Then for nine years, as a specially assigned FBI agent stood by as an official censor, Zimbalist filmed a weekly TV installment that inflated, exaggerated and often distorted the Bureau's role as a crime-fighting organization.

Ultimately, by setting standards and creating symbols that the real-life FBI could not possibly match, such characterizations did the agency (and the country) a great disservice. But the same can be said of "The Private Files," the logical and clumsy product of a de-Hooverized political political system.

A realistic and more balanced film portrayal of Hoover and his impact will obviously have to come later, in calmer times.

In the meantime, the great shame is that the Old Guard within the FBI - the loyal lieutenants of Hoover who still obey his unwritten rules and control much of what happens at FBI headquarters in Washington - will probably use this firm as evidence to support their view that uncontrolled access to the Bureau (such as that which Cohen purports to have had) can only lead to no good. They are wrong, of course, but so it this firm.

(Sanford J. Ungar, managing editor of Foreign Policy magazine, is the author of FBI: An Uncensored Look Behind the Walls.)