No Man's Land, or Pit. A huge array of private residential buildings, narrow winding streets that are not on the map, and a gloomy population that does not have a residence permit. Even the police are afraid to come here after dark... This is where Katya Mazurova, an investigator from the Investigative Committee, was born. Once upon a time, a serial killer appeared in the Pit. Among his victims was Katya’s older sister. Then the Mazurovs fled from the Pit, never to remember the nightmare they had experienced. But now, 18 years later, Evil has returned.