American professor Dr. Diana Bishop discovers an unusual book while researching 17th century chemistry at Oxford’s Bodleian Library. The book, known as Ashmole 782, is a “thick quarto-size manuscript” bound in calfskin (1), and part of Bodleian’s collection of works by the 17th century alchemist, Elias Ashmole. Diana senses immediately that the book has supernatural power. Diana is a witch, although she rejects this part of her heritage. Diana’s mother, Rebecca Bishop, was a talented witch who married Stephen Proctor, an equally powerful wizard. Diana’s Aunt Sarah, her mother’s sister, is also a witch, and the Bishops can trace their family history back to Bridget Bishop, the first witch executed during the Salem witch trials. Diana resists her own magical powers because she blames her parents’ magic for their disappearance and death in Africa. Instead, Diana relies on research and science to direct her own life. Diana doesn’t need her magic to be successful in the academic world: She is a published author and tenured faculty member at Yale. Another visiting American scholar and fellow witch, Gillian Chamberlain, tries unsuccessfully to get Diana to join the local coven.