A Discovery of Witches - Deborah Harkness

Diana Bishop, a young historian (and a witch), discovers an enchanted manuscript at the Bodleian Library at Oxford. The text, known as "Ashmole 782," turns out to be a coveted treasure lost for centuries, and she is the first and only creature who has met the terms of its spell. Her discovery sets the supernatural world spinning, and she soon finds an ally in Matthew Clairmont, a 1,500 year old vampire. A Discovery of Witches debuted at #2 on the hardcover New York Times bestsellers list.