A West German businessman Friedrich Schmidt is arriving to Czechoslovakia with private mission and mission for Intelligence service. He wants to settle the old event from the time of the Second World War when he as a student of the Czech grammar school in the town of Kostelec took part at the denunciation of his schoolmate Pavel Richter. Pavel was during the period of Nazi terror following the assassination of Acting Reich Protector of Bohemia and Moravia Heydrich executed. Schmidt has also to enter into relations with persons suitable for cooperation with the West Intelligence service. Schmidt - earlier, before the German occupation Smíd - meets the schoolmates and endeavors to avert suspicion that arose already at the time of the tragic event.