By Rebecca Stott

Spiegel & Grau. 304 pp. $24.95

To concoct this cerebral thriller about 17th-century alchemy, Rebecca Stott grinds two parts of historical research into a fine powder, folds in some human blood, adds a pinch of the occult, and heats the mixture over an open flame. By the time Ghostwalk begins to boil, it's a hypnotic brew of speculation, intrigue and murder.

Stott teaches English at Cambridge University, where Ghostwalk takes place, but she's grown interested in the history of science, and her first novel sets off in search of the philosopher's stone, that elusive substance that can transform base facts into golden fiction. Her story rests on the striking incongruity of Isaac Newton's career: The genius we remember as the author of Principia, the inventor of calculus, arguably the father of the Enlightenment, wasted most of his life feverishly searching for alchemic secrets in the Bible and other ancient texts. Despite his revolutionary work on the nature of light and gravity, he saw no distinction between what we would call science and the occult. And in the same way, Ghostwalk blends history and make-believe. It's outlandish and devilishly plausible.

At the opening, Cameron Brown, a top neuroscientist, discovers his mother drowned in a lake, clutching a glass prism. She was an iconoclastic historian finishing a biography of Newton. Determined to see the book published, Cameron begs his ex-lover, a historian named Lydia Brooke, to pick up his mother's research and ghostwrite the final chapters. Lydia claims she no longer has feelings for Cameron, but who can resist a serial adulterer in a lab coat? She accepts the assignment, moves into his mother's remote cabin and begins reading her unfinished manuscript.

Although Stott obviously knows a great deal about Newton, she should have brushed up on his First Law: A story in motion should stay in motion. But after a deliciously macabre preface, Ghostwalk loses its momentum, becomes an object at rest and tends to stay at rest till about page 50, when it finally starts up again. This slow exposition will flush out most of the Da Vinci Code readers, but persist: You'll be enthralled by what develops.

Lydia learns that before Cameron's mother died, she had been driven half mad by what she had discovered about a string of suspicious deaths around Cambridge in the mid-17th century. Apparently, Newton compiled a rather ordinary academic record as a student, but he managed to secure an appointment at Trinity College after a surprising number of positions suddenly "opened up." Meanwhile, modern-day Cambridge is being terrorized by violent animal rights activists who identify themselves as "NABED" -- a code word from one of Newton's alchemic journals.

Lydia becomes convinced that there's a connection between the deaths that facilitated Newton's professional success three centuries ago and the attacks on Cameron's research lab. But the nature of that connection is at first so obscure and then so ludicrous that she resists believing it. Stott drops mystical elements into the story with such subtlety that you're likely to dismiss them (just as Lydia does) as tricks of her tired mind: a strange aroma, a stain that fades and reappears, "a pool of light that moved in strange ways across a wall," a bound cat mutilated on the doorstep.

Okay, that last one isn't so subtle, but eventually Lydia realizes that she's working in a place where "the natural bleeds into the supernatural." She's caught "between the seventeenth century and the twenty-first, between skepticism and belief." In an unnerving, strangely beautiful scene, she seems to see the outlines of 17th-century Cambridge and catch a glimpse of a red-cloaked professor. Does the hardworking historian just need a nap, or has a 360-year-old mathematician taken a deadly interest in her? Will she be hit on the head by an apple or by an apple cart?

Among the surprising pleasures of Ghostwalk are a couple of chapters from the biography in progress -- complete with footnotes to actual histories and archival material. The section that explains how a glass prism was manufactured in Venice and eventually delivered to Newton in the 1660s is particularly fascinating and endows the novel with the kind of authenticity that makes its more speculative elements even creepier. And who's to say the distinction between science and the occult isn't collapsing? Lydia notes that quantum mechanics speaks of "charms," "spooky action" and "non-local entanglement." A 17th-century alchemist would feel right at home in modern-day Cambridge.

And apparently one of them is trying that out, but I'm not giving anything away. I'm not even sure I could (and I was taking notes). By the final chapter, Stott's elegant subtlety has been transmuted into a violent swirl of reversals and revelations that would defy Newton's calculus. You can't help but feel swept away. ·

Ron Charles is a senior editor of Book World.