The ambitious scientist Franz Walter doesn't hesitate when he is promised a professorship at the university. He immediately accepts, pledges absolute loyalty to the system and agrees to work for the GDR's foreign intelligence service until he can take up his new position. Together with his colleague Dirk, he is sent on foreign assignments to West Germany. Franz soon has to use blackmail to get innocent people to talk. But his superiors go even further: GDR refugees and their relatives are targeted to be psychologically destroyed, forged letters, medical diagnoses, surveillance and wiretapping are on the agenda. However, this is more than Franz can bear: he feels powerless and increasingly isolates himself. When he then decides to steal secret documents for a later defection to the West, this results in an unfortunate chain reaction leading to his arrest and ultimately to his execution...