The story centres around Julie d'Aubigny, a historical French opera singer and swordswoman. It features her life and adventures as a vampire in the 1750s, fifty years after her public 'death'. Driven by vengeance over the death of a woman she loved during her mortal life, she hunts down other vampires with the aid of her companions, a pair of wealthy Senegalese twins who travel with her for the thrill of adventure. The story brings her from Constantintople to London, where she crosses paths with Arnold Brennan, an English clergyman who is just discovering that vampires exist following the murder of his father.