The Great Patriotic War. While the Red Army troops are carrying out successful offensives, a team of Soviet saboteurs is engaged in subversive activities in the German end.  Fascist echelons being destroyed one by one, and the group of demolitions remains elusive. And then the Germans organize a large-scale military operation to neutralize them ... Events in the picture unfold in the territory occupied by the Germans, when Russian people, each fighting for their fatherland, find themselves on opposite sides of the barricade. Russian partisan sappers are fighting with the Germans and blowing up their equipment and military  trains, and nearby in the camps, captured soldiers are forced to work for the Nazis and teach them sapper art.