Heavy on the supernatural; light on the historical fiction

PhD candidate Connie Goodwin is preparing her late grandmother's long-abandoned Marblehead, Mass., house for sale when she finds a key in the family Bible. Rolled up inside the antique key is a slip of paper with a name on it: Deliverance Dane.
Connie decides she is going to find out all she can about Deliverance Dane, whose story is told in parallel to her own. Deliverance Dane is a Salem-area resident in 1692 ... three hundred years prior to Connie's time ... who is caught up in the witch trial hysteria. Connie decides to do her thesis on Deliverance's "physick book," which she finds discussed in a number of references, assuming she can find the tome in question.
Strange things begin happening around Connie as she gets deeper into her research; there is a much larger supernatural element to this book than there is of historical fiction.
I enjoyed it once I was able to take it as a light read rather than a work of serious historical fiction, to be honest. The Deliverance Dane portions of the book were almost always more interesting than the foibles of 1991's Connie.