The corpse of one of the fighters of a local criminal group was discovered outside the city. The investigator is ready to write off the incident as an ordinary gang war and close the case, but Stepan Krucha has a different opinion. The victim's gun is stolen, which means the series of murders may continue. Stepan’s instinct did not let him down: the next target was the only witness to the out-of-town incident, who managed to tell Krucha before his death that he saw the victim that day along with the possible killer. Having the signs of a criminal in hand, the operative narrows down the search, but suddenly realizes that he himself is becoming the target of an invisible killer...