"Night Monster". This is the nickname the police gave to the mysterious criminal committing murders in a large clinic. He covers the eyes of his victims with brass circles with the image of the rod of Hermes. What is the meaning of his strange “messages”? And most importantly, why does each of the deaths look like the result of an accident or an ordinary medical error? Lindsey Boxer and her friends are the best team in the investigation of murders with from the times of Sherlock Holmes and Dr. Watson - they begin an investigation and come to a terrible conclusion: all the evidence points to the fact that the maniac is one of the clinic staff. The next victim could be any patient...