Deep in the stacks of Oxford's Bodleian Library, young scholar Diana Bishop unwittingly calls up a bewitched alchemical manuscript in the course of her research. Descended from an old and distinguished line of witches, Diana wants nothing to do with sorcery, so she banishes the book to the stacks. But her discovery sets a fantastical underworld stirring, and a horde of daemons, witches, and vampires soon descends upon the library.