Eduard Avdonin, a sable fur specialist, is murdered in Siberia, in one of the fur reserves. The case is assigned to senior investigator Dagurova of the prosecutor's office. She rejects one suspect after another. Having found out that the deceased was a poacher, Dagurova soon comes to the conclusion that the murder was committed by the director of the reserve Gai, who organized the illegal sale of furs abroad. Now the lives of the investigator and witnesses are in danger.