Forensic psychiatrist Lyubavin turns to his goddaughter and colleague psychotherapist Nelly Tarle with a strange request: to get a job in a psychiatric boarding school called “Blue Hill”. Several years ago, Lyubavin was involved in a medical examination of a man who had killed pedestrians. The professor declared him sane, after which the culprit of the accident was re-examined at Blue Hill with the opposite result, avoiding criminal liability. Professor Lyubavin’s reputation was questioned for the second time when a witness in a high-profile criminal case also ended up in Blue Gorka with a psychiatric diagnosis, and soon died in an accident. It is clear that strange things are happening in the boarding school, but only by getting there can you find out the truth. And Nelly agrees to become a “sent Cossack”...