In search of an enchanted alchemical manuscript, Diana Bishop, a historian from Oxford and an heiress to witches, together with Matthew Clermont, a vampire, is transferred from the 21st century to London in 1590, where he enters the world of alchemy and magic and meets Matthew's old friends from the mystical School of the Night. It is in old London that it is necessary to find a witch who will teach Diana to manage her hereditary abilities, and Matthew is forced to confront his own past, which, as it seemed to him, was left behind. In addition, they are drawn into the battle of supernatural forces, unfolding around the mysterious manuscript "Ashmol-782."