IN LATE 1971, the Chinese government in Peking announced that Mao Tse-tung's erstwhile successor, Lin Biao, had died in a Mongolian air crash while fleeing China after failing to kill Mao and seize power for himself. Some details and much accusatory material later emerged, but the matter remained a mystery, even after the 1979 trial of Lin's remaining associates and a more detailed accounting of the lurid events behind the Cultural Revolutionary power struggle.

Meanwhile, all kinds of rumors circulated in China and abroad. Lin Biao was said not to have been on the downed jetliner at all. Instead, Mao was rumored to have killed him in Peking or thrown him in prison. Some asserted that the plane was shot down by Chinese fighters ordered out by Chou En-lai. The plane in question perhaps did not take off from Beidaihe, as the regime asserted, but from Peking itself, thus casting suspicion on the official story. Lin Liheng, Lin Biao's daughter, allegedly betrayed her father by refusing to board the getaway plane and then telephoning Chou, who ordered the air force to give chase. Lin Liguo, his son and mastermind of the anti-Mao plot, allegedly ran a sex shop as a means of hunting up eligible mates to serve him after he succeeded his ailing father. If one were to believe these and other tales, one could well conclude that the Chinese Communist Party engaged in a gigantic cover-up to hide the real nature of Maoism and the Byzantine nature of Chinese politics.

Now comes a full-blown manuscript, allegedly written under a pseudonym by a Chinese official still in the country, asserting that the official story is an elaborate hoax and the reality of the 1971 events was quite different. In essence, "Yao Ming-le" says that, based on highly classified documents to which he had access, Lin Liguo twice tried to kill Mao by rocket ambushes of the chairman's train, and was held back on both occasions by Lin Biao himself. Mao, discovering these plots against his life, lured Lin Biao and his wife to a last supper at his opulent Peking residence, after which he neatly demonstrated how an ambush should be conducted by carrying out a missile/machine gun attack against Lin's limousine as it descended from Mao's suburban mountain retreat. The Lins were burned to death. Once Lin's fate was understood by his son, he raced to commandeer an air force Trident jetliner but it was intercepted and crashed later in Mongolia. A helicopter, carrying four of Lin's top aides, also tried to escape, but was forced down and they were all captured.

According to Yao's scenario, the plot was engendered by Lin Biao himself and, despite his son's excessive zeal and going beyond his father's order, would probably have succeeded if Lin had chosen to carry it out. There was no doubt, for instance, that Mao's train would have been destroyed by the planned rocket attacks. If the Soviet Union had cooperated by working with Lin to do its part in the coup attempt planned in late September or by actually invading China after Lin's forces had deliberately provoked them, Mao might have been forced to expose himself to Lin's death plot. The reason neither the train ambushes nor the invasion-induced scenario worked, according to Yao, was that Lin hesitated at the last minute (literally, in the case of the ambushes) and that Mao somehow found out what Lin was up to and preempted him. It was thus a contest of personalities: the cautious, carefully planning Lin versus the more flamboyant, risk-taking Mao. In the end the more Machiavellian won. Each knew the other was out to kill him; Mao merely was more ruthless. He also knew Lin's limitations better, and traded on Lin's previous half century of loyalty to do him in

What are we to make of this fantastic story? Should we believe the general outline as well as, for instance, the detailed description of Mao's Peking residence and his mountain shelter outside the city and the ribald sex scenes? Should we take at face value quoted conversations, thought-patterns reported as facts, detailed lists of participants and military units, hour-by-hour movements of the various principals, life histories of even minor characters, and even the comparative emotional states of at least a hundred people? Should we acquiesce in the notion that any Chinese official could have had the total degree of access Yao claims and then possessed the time to write such a smooth manuscript, all without being caught? Should we allow to pass a text that, while purportedly claiming to base itself on the most closely held inner-party documents, does not bring forth a single document as corroborating evidence? Should we accept the statements of a man of whom we know absolutely nothing? What about the translator?: Even he/she is an unperson.

This book reads too well for a text allegedly furtively brought together on the basis of for-the-drawer diaries. memory-only cullings from classified documents, and knowledge of only certain portions of the lives of principal actors. It sounds like a novel, not an expos,e. It reads too well in English, and if one attempts to translate back into Chinese, one doesn't get something that sounds like an original. The suspicion arises, therefore, that the book is a forgery, possibly the cooperative work of forces (probably outside the Mainland) unfriendly to the Peking regime and (say) a disgruntled Western journalist.

On the other hand, the general outline is not implausible. It captures personalities reasonably accurately. It is not blatantly inconsistent internally (there are such instances but their magnitude and number are not serious). It dovetails with the official Chinese explanation at points where facts can be checked. In sum, we must remain agnostic; it is neither better nor worse than the official explanation. One test of its authenticity is how Peking reacts to its publication (which, it should be noted, is being done in seven languages simultaneously, so confident is Knopf of the story's veracity). If there is a vociferous denial and reiteration of the official story, the revisionist case weakens. If there is a pro forma rejection followed by discrete silence, Yao's case is strengthened.

In the end, one should be more than a little cautious. This is, after all, the age of the expert forger and Chinese are no less adept than Europeans at this art. But perhaps the more important test is the one of plausibility. Could Lin really have thought he could have killed Mao by inducing him into the "Jade Mountain Stronghold" shelter complex and then gassing him to death? Would Mao really have believed reports of Soviet invasions? What if the Russians refused to play their part? Was Mao really capable of killing Lin so callously after such a long career together? Why not just have him arrested? Did Lin believe that the Chinese people would have welcomed Mao's assassination, an overnight reconciliation with Moscow, and a pledge to unite against America on the eve of Sino-American rapprochement? Would, finally, Peking have risked such an elaborate cover story, when surely it would eventually have been found out and thus call into question all of its subsequent pronouncements on diverse topics? Even totalitarian regimes have to retain a healthy degree of internal and international support.

In sum, this book is interesting reading. But it should be treated as fiction, not fact, until further evidence is at hand.