An accidental crime, leads Kamenskaya to a closed research institute, where experiments are conducted with secret developments that affect the psyche of people. Nastya notes a strange pattern of crimes occurring in the area of ​​the institution's location. And after the first serious contact with the leadership of the scientific research institute, she is subjected to an attempt. When this happens again, it is saved by an unknown person who introduced himself as a passerby to random people. Kamenska, luring the savior to her home, "splits" this guardian angel, who turned out to be an employee of the FSB. There, to the very top, and led the threads of the investigation of the murder of one of the Institute's scientists ...