This biography explores the life of the 16th-century ‘Blood Countess’ of Hungary, Erzs bet B thory. Reputed to be both a vampire and the world’s worst female serial killer, she allegedly bathed in the blood of her 650 victims. Based on newly-found source material, translated into English for the first time, this book explores the actual life and trial of Countess B thory, through letters, documents, and trial transcripts.