When a serial killer begins stalking the streets of London's East End, his grisly dealings are overshadowed by the hysteria surrounding Jack the Ripper's Whitechapel crimes, enabling the seemingly supernatural killer's activities to spread unchecked. Dr. Thomas Bond, a police surgeon assisting in the investigation, responds to the carnage he sees by ever-more-frequent visits to an opium den. His search for the man leaving parts of women strewn around the city, including in the basement of the new location for Scotland Yard, leads him to team with some unusual allies-and to a truth about the crimes and their connection to a Polish legend that he finds almost impossible to believe.