A city is in panic: a mysterious extortionist-killer sends letters with threats to the families of teenage girls. If he isn’t paid the specified sum on time, the letter says, the girl will be raped and murdered. And these aren’t empty threats: a woman paid the extortionist the needed amount—yet her daughter was killed anyway. Desperate, the mother turned to a private detective, Tatiana Ivanova, who from the very first steps of the investigation concluded that the criminal’s actions are completely unpredictable and illogical. That can only mean one thing: either a madman is working here—or someone trying to pass as one…