When a nurse is murdered and another disappears during a hospital blackout, Detective Inspector Irene Huss of the Violent Crimes Unit struggles with a report by the crime's only witness, who claims she saw a nurse who died sixty years earlier.

"He watches the women from the shadows. He has an understanding with them; as long as they follow his rules, they are safe. But when they sin, he sentences them to death. A woman is found dead in a cemetery, strangled and covered in plastic. A thorough examination of the corpse reveals that the killer left behind no evidence. But just a few days before her death, the victim received a flower, an unintelligible note, and a photograph of herself. Detective...