First, let me say that The Sacred Pool is an absolutely riveting, well-written book. Second, let me confess that I would never have read it if my editor had not assigned it to me.

Why? The lurid cover. Forget the famous aphorism, because books are judged by their covers. Had I accidentally found myself in the Barnes & Noble aisle dedicated to such books, and seen the cartoonish jacket painting of two medieval maidens in a forest - one a see-through phantom standing in a pool of water - with low-cut bodices and long black tresses (and oddly masculine hands at their sides), I would have immediately dismissed the book as substandard reading from a particular genre: science fiction/fantasy.

Genre books, to readers with high foreheads and degrees in English, are not really literature. They may get reviewed in newspapers, but it's inevitably in a small column devoted to their "type": mystery/thriller, sci-fi/fantasy, horror.

There is, of course, a reason most of these books stay stuck in their categories. Many are badly written and formulaic, with plots so predictable it often seems that only the names change. But avid readers of genre books like this familiarity; it satisfies a craving just the way a quarter-pounder with cheese does. But you won't find McDonald's in the Zagat restaurant guide, and you usually won't find a genre book in a literary book review.

Exceptions that prove the rule: J. K. Rowling, Stephen King, Ursula K. LeGuin, and a handful of other writers have leapt out of their respective genres and into the mainstream. L. Warren Douglas may join their ranks. The Sacred Pool, set in Provence early in the Middle Ages, surely deserves a better fate.

Douglas chronicles the period when paganism gave way to Christianity, when witches succumbed to priests, and sacred stones transmuted into cathedrals. His heroine, Pierrette, is a little girl when the story begins. Her mother, a masc, or witch of limited power, is beaten to death by townspeople afraid of sorcery. Pierrette's father is too afraid to defend his wife; her sister, Marie, blocks out the murder. Only Pierrette remembers that evening and the sprite Guihen who watched over her and her sister while the mob raged nearby.

Disguised as a boy so the town's Gaulish ruler cannot claim her father's olive grove, Pierrette studies theology with the local priest, and sorcery with the local magus. She has gifts far beyond her mother's simple magic.

Douglas shows a vast knowledge of Proven?al folklore and history. Guihen and his wildman compatriot, Yan Oors, "John of the Bears," appear as full-fleshed characters. Pagan gods are eaten by the Christian devil, but none exists without belief.

Pierrette begins to understand why the power of the pagan magic is waning just as the power of the Christian myth waxes. And yet, as Douglas shows, both belief systems stem from a common root.

Pierrette meets an abbess who reminds her strikingly of the deity of all nature, the Earth's mother, called Ma. Yet the abbess is Christian:

[Pierrette] hesitated to claim that Christian prayers to Mary were heard by the spirit who listened by the sacred pool . . . but Ma was also virginal, a mother, and her offspring died and were reborn. "I'm not ignorant of the old ways, girl," said the abbess. "I sprang from the same rocky soil, the same clear sunlight, as you. Is it any wonder that the three Marys who brought Jesus' words to this land were welcomed? Who were they but messengers of a deity we already knew - yet with a new message, indeed.

At this point, Douglas interpolates an important piece of biblical history into the tale: that three of the Christian Marys (Mary Magdalen; Mary, the mother of the disciple James; and Mary, the mother of James the Elder and John) who left the Holy Land after Jesus' crucifixion, sailed to the Roman province of Gaul, and settled in the town near Marseilles that still bears their name: Saintes-Maries-de-la-Mer.

His heroine, who has learned how to "part the veil" of time, must return to their era in order to exorcise a demon burgeoning in her own. The sophisticated contemplation of time as a wheel (a popular concept in the Middle Ages) and the consequences of breaking a spoke of that wheel; faith vs. scientific reasoning (skepticism kills magic, just as logical explanations subvert faith); the history of Provence, its folklore and culture; and a compelling tale with well-rounded characters - not only Pierrette, but also sister Marie and father Gilles, Father Otho, magus Anselm, the Burgundian knight Jerome, the gypsy Marah, and assorted minor deities and primitives of prehistoric Provence - make this a book well worth reading.

Head to the science fiction/fantasy section of your local bookstore and buy a copy, no matter how stupid you feel carrying it to the cashier's counter. You will be glad you did, and I can confidently predict more reading pleasure in your future: The Sacred Pool is only the first in a trilogy about Pierrette the Sorceress.

Susan Balee regularly reviews books for The Inquirer and the Hudson Review.

Published by the Philadelphia Inquirer, 01-21-2001