BURIED SECRETS; A True Story of Serial Murder, Black Magic, and Drug-Running On the U.S Border By Edward Humes Dutton. 412 pp. $21.95

BURIED SECRETS documents the all-too-recent rise, reign and fall of Adolfo de Jesus Constanzo, a high priest whose religion -- Palo Mayombe -- required that he and his followers inflict suffering and death. In the rituals of Palo Mayombe, we learn, it is "important that the offering die in confusion and pain and, most of all, in fear. A soul taken in violence and terror could be captured and used by the priest, turned into a powerful, angry servant . . ." Accordingly, Constanzo courted the screams of his human victims with long bouts of torture.

Santeria, a Latin American religion that merges African gods and Christian saints, is the root from which the malignant Palo Mayombe derives. "The most powerful spells in Santeria and Palo Mayombe," Humes tells us, "require bodily fluids, such as sperm or blood, which the believers consider sacred. Even the most benevolent ceremonies and spells require the blood of animals -- usually chickens -- to be ritually shed and offered to the orishas or the spirits of the dead. This is considered a divine act, not evil -- by most." Thus Santeria -- which is a widespread religion in Cuba and in Latino communities here in the United States -- prepared the way.

Constanzo's followers were, in the main, drug runners and dealers seeking to use Palo Mayombe's dark powers for protection. Their unquestioning belief that participation in ritual bloodletting would protect them, even render them invisible, led to their unmasking and arrest. It also solved the mystery of a young college student's disappearance in the border town of Matamoros, Mexico.

In mid-March 1989, Mark Kilroy, a junior at the University of Texas, was one of thousands of kids mobbing the wide-open Matamoros bars during spring break. Many of the revelers were still on the street when Mark and his buddies began wobbling back toward the international bridge and Brownsville. Inexplicably, Mark got separated from his friends and never made it across.

Kilroy was but one of "sixty open cases of desaparecedos -- the disappeared -- on the books of the Matamoros city police from the first three months of 1989 alone." But Mark was a gringo who had an uncle working for U.S. Customs. There were strings to pull. An all-out investigation, with attendant publicity, was launched on both the Mexican and the American sides.

This investigation, despite its unprecedented size and scope, yielded nothing -- or so it appeared as April Fools' Day, more than two weeks after Kilroy's disappearance, dawned.

On that day, one of Constanzo's henchmen blithely drove through a checkpoint that Mexican federal drug agents had set up to search cars and trucks for narcotics, a checkpoint marked by bright orange cones and warning signs.

When agents tailed the man, they were led to Rancho Santa Elena. Here Kilroy and several others who had been offered to Constanzo's savage Palo Mayombe gods lay buried, a fact revealed when smugglers captured at the ranch were questioned.

The excavations and their grim yields made even staid family newspapers read like sensation-seeking tabloids. After Kilroy's, 14 more bodies were discovered on and around the place. Thirty additional murders in other parts of Mexico (including 16 ritually killed children under the age of 16 that are catalogued in this account as "suspected but not proven") have since been attributed to the high priest.

A month later, Constanzo himself was found dead in the closet of an apartment in Mexico City -- gunned down at his own request by one of his followers as a shootout with police ensued in the streets four floors below. Constanzo faced death with unblinking indifference (literally: the autopsy revealed that a bullet had pierced his eye, but not his eyelid). "Don't worry," Constanzo is alleged to have said just before he died. "I'll be back." EDWARD HUMES, an investigative reporter who has won a Pulitzer Prize, has done a masterful job of sorting and reweaving the many threads of this tale. His documentation alone reveals how thoroughly he's gathered and sifted the facts (indeed, one wishes that the footnotes had appeared on the bottom of the pages because they, like the text itself, have a must-read quality).

What is more, Humes looks beneath the story he tells, examining the role of black magic and the persistence of Palo Mayombe, largely in Florida, where Adolfo de Jesus Constanzo was born and raised.

But Palo Mayombe is elsewhere, too. We are told that an "explosion of crimes involving these religions -- drug dealing, grave robbing, extortion, and murder -- has been reported nationwide." Artifacts used in Palo Mayombe -- the awful cauldrons of blood and flesh and bone known as ngangas, for instance -- have been found in this country and in Mexico as well. Indeed, Constanzo's own nganga was spirited away, presumably for future use, by one of the believers who escaped. According to the testimony of anthropologists who have served as police consultants on ritual crime, Constanzo was not just making up his religious practices as he went along. There are apostles aplenty, enough to carry on where he left off. This makes for a chilling conclusion to a chilling book. Carolyn Banks is the author of several suspense novels and writes frequently about the true-crime genre.