By Anne Rice

Knopf. 965 pp. $22.95

WHAT WITH idiotic incantations like "Double, double toil and trouble," tacky costumes and unseemly cackling, witches -- from the three dames in "Macbeth" to Witch Hazel in "Little Lulu" -- are a pretty pathetic group. Sisterhood is not very powerful. Sure, witches get to copulate with the devil and ride on brooms and turn milk sour, but for all their magic, they can't even rid themselves of those ugly giant nose warts. For every adorable twitch Elizabeth Montgomery did on the television series "Bewitched," for each revisionist interpretation in books like Erica Jong's "Witches," there are a hundred Halloween hags.

But none in this novel: Rowan Mayfair is one beaut of a witch. She is not merely blonde, rich, sensual and lovely. She is a woman of accomplishment, a gifted and compassionate neurosurgeon, an adventurous sailor, a tough-minded feminist.

Once again, as she did in her superb Interview With a Vampire, author Anne Rice offers more than just a story; she creates myth. In The Witching Hour, she presents a rich, complicated universe that operates by both natural and supernatural law, and she does so with such consummate skill that halfway through the novel, even the most skeptical reader has no trouble believing in the existence of witches and -- yes -- in The Man, Lasher, the devil incarnate (well, for most of the book, the semi-incarnate). Her accomplishment is so marvelous that the reader is doubly angry at the unfair, up-in-the-air ending. But more carping later: first, applause.

A funny thing about the Mayfair family. They have fantastic ESP. And luck. True, a couple of early Mayfairs were burned at the stake, but over the last few centuries they seem to have become more and more fortunate. They are wealthy beyond comprehension. Beautiful, too, despite an odd family predilection for inbreeding. And in each generation, the woman who heads the clan -- and wears the incredible Mayfair emerald -- is seen in the company of a handsome, brown-eyed man, a man who is there one moment and the next, appears to . . . disappear.

But Rowan has no idea she is a witch. Taken from her (heavily sedated) mother as soon as she was born, and sent away from the family home in New Orleans, she grew up thinking herself to be the normal child of a normal, wealthy San Francisco family. Well, sort of normal. An odd thing happened to a school friend who made Rowan very angry. The friend died. And so, mysteriously, did a few others, including her cold, manipulative, seductive stinker of a stepfather. Also, Rowan's gifts as a surgeon cannot be explained merely by hard work and native talent. As she operates, she can "see" the structure of the nerves themselves. She "knows" if a patient has a chance to live. And she has an incredible healing power. Rowan is too intelligent not to question these strange abilities, but she cannot find an answer.

Neither can handsome, macho Michael Curry. A San Francisco businessman, a contractor who specializes in renovating old houses, he nearly dies from drowning. Or perhaps he does die. In any case, when he wakens in the hospital, he discovers he has a strange and frightening gift: the ability to receive impressions from any object he touches. But there is more to Michael than this mysterious and unique talent. As a child in New Orleans (yes, New Orleans) he caught glimpses of a handsome brown-eyed man who had the ability to suddenly . . . not be there.

Anne Rice weaves together the story and history of these two attractive heroes with that of a centuries-old secret organization for the study of supernatural phenomena, the Talamasca. She also provides a fascinating genealogy of witches, an inquiry into the nature of "the devil," even a scientific explanation for magical powers. There is more. Her sex scenes are genuinely sexy. And, as in her vampire chronicle and in her fine novel about the castrati, Cry to Heaven, she evokes settings with extraordinary detail and deftness. Her New Orleans is so hot and moist and appealingly decadent that the reader can almost sniff the perfume of its mildew. Her San Francisco is wonderfully rendered, in all its chill sophistication.

But the ending! Rice, usually the most accomplished of novelists, doesn't play fair with the reader. In books like The Witching Hour, books that fall into a genre, the writer is obliged to play by the rules of that genre, although the play should be as original, as fresh and unexpected as possible. The writer of a whodunit, for example, must allow the detective to catch the murderer. The writer of a supernatural novel has to let good ultimately triumph over evil, as Stephen King does in his epic, The Stand. If an author insists on breaking the rules then he or she must do it with such brilliance that the reader feels awed and grateful, not resentful. Rice fails in this regard. She does everything except put a "to be continued" announcement at the end, hinting that maybe, in the next novel or the one after, Rowan and Michael -- and the whole world -- may come to grips with The Man.

But let's be fair to Anne Rice. Although this reader was so angry at the ending of The Witching Hour that she would gladly have gone out and put a silver stake through the heart of its author, this reader refrained. After all, she wants Rice to live to write her next novel. And rest assured, this reader will be the first one in line at the bookstore when that damned Sequel From Hell comes out.

Susan Isaacs's new novel, "Magic Hour," will be out early next year.