WILLIAM C. SULLIVAN's 30 years in the Federal Bureau of Investigation came to an end, not unexpectedly, on October 1, 1971, when he arrived at his office at the Department of Justice and found that the locks had been changed and that his name had been removed from the door. This was one day after he had engaged in a shouting match with the director, the late J. Edgar Hoover, and shortly after he had written Hoover a letter complaining that the top echelons of the Bureau were bloated with 'Yes men,' 'rubber stamps,' 'apple polishers,' flatterers, self-promoters and timid, cringing, frightened sycophants, who were too afraid of the director to speak their own minds.

This was all true, of course, just as it was true that it had taken Sullivan 30 years to summon up the courage to say it. But he said it often in the years that followed, and from then until he was killed in a hunting accident in November, 1977, he conducted a sort of guerrilla warfare against the Hoover legend, emerging from his New Hampshire retirement, from time to time, to issue blasts at the insanities that marked Hoover's Bureau and the alleged personality quirks of the director himself.

Sullivan was a short, wiry man, whose rapid speech pattern was marked both with a trace of a Yankee accent and with some of the 19th-century speech mannerisms still in use in the Massachusetts region where he was born. People he disliked were "villians" or "rascals," and when you heard him say it you were reminded of Bernard DeVoto's observation that, in the hill country of New England, where life is a struggle, and necessarily a losing one, the word "fool" retains its ancient savor.

Hoover, Sullivan maintained, was not only a "fool" but a petty, bigoted, small-minded man, who kept a black retainer at the ready with a fly swatter to clear the office of insects, who had engaged in blackmail and character assassination for almost half a centruy, and who, on top of that, was an inept and short-sighted administrator, and "one of the greatest free-loaders this country has ever seen."

There is little doubt that the words in the book are Bill Sullivan's words. Bill Brown, his co-author, says that the manuscript, which apparently was assembled largely from tape recordings and Sullivan's own written notes, was nearing final form at the time of Sullivan's death. Anyone who ever heard Sullivan speak can almost hear his voice coming right out of the pages.

But it is less clear that this is Bill Sullivan's book, because while the criticisms of Hoover and the Bureau are familiar to anyone who knew Sullivan in his later years, the book conveys an intensity -- almost an obsession -- that was not as apparent in the man himself.

Sullivan could be emotional on the subject of Hoover; in fact, many of his former colleagues in the Bureau went to some lengths to try to persuade reporters that he couldn't be trusted on the subject, calling him "Crazy Billy," and suggesting he had become irrational on any matters relating to his former boss. But none denied that he also was the closest thing the Bureau had to a resident intellectual during the Hoover years: A thoughtful, articulate student of communism and other mass movements, whose first ambition had been to teach in a small New England college, and who, in casual conversation, displayed an impressive knowledge of his history and of the social order of the world around him.

This book, unfortunately, reflects little of this scholarship and insight, and adds up to little more than a diatribe against Hoover and the Bureau that he created, coupled with a scattering of self-serving (and not entirely believable) justifications for Sullivan's having stayed in the organization for so long, and for being a part of so many of the things -- the anti-communist hysteria, the harassment of political and civil rights groups, among them -- that he later found reason to denounce Hoover for. (It should be noted, in this context, that Sullivan was the sort of person who, while in government, believed that the government should have great powers to involve itself in people's lives, but who, after retirement to New Hampshire, questioned the right of the state to make him have his car inspection each year.)

Also, Sullivan had to be cautious in assigning any blame to himself, because, by the time of his death, he had been named in civil suits stemming from almost every infraction, real or imagined, that the Bureau had committed against citizens since World War II, and could rarely step out of his house without being served with another subpoena. In short, he was aware that anything he said about his own activities might well be used against him in court.

Ten years ago, this book most likely would have kicked hjup a storm of controversey, detailing as it does Hoover's alleged use of the bureau to spy on political figures (such as Adlai Stevenson), his passion for pornography (Sullivan claims Hoover had a standing rule that all compromising photographs obtained by agents be routed immediately through his office), and his squandering of the Bureau's limited resources on trivial crimes.

But in recent years, all this has been done, and done with more objectivity and scholarship (The FBI, by Sanford Ungar), greater insight (Brick Agent , by Anthony Villano), and with a more skilled handling of the theater-of-the-absurd atmosphere that colored the bureau (No Left Turns , by Joseph Schott.)

There is some worthwhile discussion in this book of the role of intelligence agencies in a complex world. There are some previously unpublished anecdotes about life with Edgar, some lively tales of little-known FBI cases, and a handful of horror stories that historians and FBI Kremlinologists will find of some interest. There also is the material for serious debate about the holds that petty tyrants can exert over basically decent men, and about the flat statement by Sullivan that "The Bureau made liars of us all -- if you didn't lie you couldn't survive." There are a good many FBI veterans who will take issue with that, and Sullivan never adequately explains how he not only managed to "survive" in such a system for so long, but actually rose almost to the top, being named the No. 3 official in the years just prior to his final break with the boss.

But the main purpose of the book appears to be neither serious history nor self-jusitifcation, nor disclosure with an intent to reform. Rather, the purpose seems to be getting even even, pure and simple, and the result is a series of assaults on Hoover and almost all his lieutenants that should cause even veteran Hoover-haters to wince.

It may be that this is precisely what Sullivan intended. The problem, of course, is that Sullivan himself now is dead, and it's not clear whether this is his book, the way that he wanted it, or whether his co-author and his editors have gone through his manuscripts and taped recollections, plucked out every anti-Hoover remark they contain, and pasted them together in one, long, bitter, rambling outburst. The book is neither as intelligent nor as sensitive or witty as Sullivan himself was, and the reader, unfortunately, has no way of knowing for sure whether it is Sullivan or his collaborators who should be blamed.