During the war, a German filtration camp Nadiya was organized in the occupied territories, where experiments on children are conducted. Of particular value are the twins – the most valuable material for experiments. And when one of the twins manages to escape from the camp, the Germans raise the alarm, trying to find the boys. This complicates the lives of residents of the nearest village, and the guerrilla unit, as well as local police. At the center of the development of the life of little Petya and a touching love story of a young couple – a policeman Andrew and the daughter of the elder Nina. Heroes repeatedly face the death of loved ones, confrontation, mistrust and deception. Those who were friends yesterday are becoming the most dangerous enemies, and those who would not be helped yesterday will open up in a new way.