This has been the season for voodoo partisans in American letters. First there was incisive essayist Michael Ventura, whose collection Shadow Dancing contains a 60-page discourse on the voodooistic origins of rock 'n' roll. Now here is brash anthropologist Wade Davis, whose first-person narrative, The Serpent and the Rainbow, claims to illuminate one of the last great secrets of the Western world: the zombie phenomenom.

Davis, who was born in British Columbia and educated at Harvard (he now lives in The Plains, Virginia), is more precisely an ethnobotanist, one who studies social uses of plants and especially the drugs they yield. Yet no dry-as-dust scholar is he. Davis has fought forest fires, dodged crossfire, and lunched on fresh termites. As you will see, he might well have called his story Romancing the Toad. (His failure to do so does not reflect any ironclad opposition to Hollywood: the book has been optioned for the inevitably "major" motion picture.)

His odyssey began in 1982, when he was 28. He was summoned to the office of his Harvard mentor, Professor Richard Schultes, whose work on curare, the Amazonian blow-dart poison, has led to its use as a muscle relaxant in surgery. Schultes had learned of two well-documented cases of zombiism -- the reanimation of seemingly dead people. Would Davis be willing to go to Haiti and ferret out their pharmacological basis? Two weeks later he was in Port-au- Prince.

He took along with him a hypothesis. "It was completely conceivable that a drug night exist which . . . would lower the metabolic state of the victim to such a level that he would be considered dead. In fact, however, the victim would remain alive, and an antidote properly administered could then restore him at the appropriate time. The medical potential of such a drug could be enormous." Before leaving the States, Davis performed enough lab work to suppose the "killing" agent might be Datura stramonium, commonly known as the "zombie's cucumber."

Actually, Davis' mojo was working backwards. The cucumber turned out to be the antidote. The poison was a combination of several inert but horrifying substances and two active ingredients: essence of Bufo marinus, a Haitian toad, for sickening the victim, and tetrodotoxin from the puffer fish, for putting him under. So virulent yet stimulating is the latter agent that Japanese gourmands, who eat puffer fish for the buzz it gives them, occasionally die from it.

Lab work back in Cambridge confirmed Davis' findings, but this chemical success pales next to his penetration of what he considers the real Haiti. Mixing bravado and deference, he managed to gain admittance to the Bizango, the secret society that has controlled rural Haiti -- and Haiti is still at least 80 percent rural -- ever since the 1804 revolution merely substituted black plutocracy for white. One of the reasons for the late Francois Duvalier's proficiency in ruling the country was his cultivation of the society and its voodoo underpinnings. He may have even been a houngan (voodoo priest) himself.

As Davis' empathy with the Haitians deepens, he rejects the stereotype of voodoo as a satanic cult given to malevolent persecution of unsuspecting victims. Rather, he decides, it is a profound and complete religion, and zombification should be seen as the punishment of wrongdoers condemned by the people's collective judgment. Be that as it may, the voodoo judicial system seems as perniciously arbitrary, a communal version of the Star Chamber.

The Serpent and the Rainbow (the title refers to a Haitian creation myth) is replte with bizarre details to titillate the curious. Davis ascribes a lewdly arcane origin to the symbology of the witch's broomstick. One vignette portrays the American writer Zora Neale Hurston dutifully undergoing the ritual imposed on would-be initiates into a New Orleans voodoo sect: "She had to lie naked for sixty-nine hours on a couch with a snakeskin touching her navel." A critical ingredient in many a voodoo ritual turns out to be pulverized baby skull.

The ease with which Davis made himself privy to Haitian arcana looks suspicious -- how could the secret society have kept its existence quiet so long if Davis could penetrate it so quickly? Yet his sober style lends such conviction to his outlandish account that in the end I found myself persuaded that zombies do come back from the dead and that Wade Davis knows how.