The film depicts the fate of the residents of an apartment block in Prague’s Jewish quarter following the invasion by German troops in 1939. Among them is an elderly widow who had once disowned her son and now wishes to bring him to Brazil; there are also the owners of a stationery shop, who are driven to ruin by the German occupiers. The caretaker Glaser, who is of German descent, also comes under pressure when his son is arrested in a communist pub. To save his own skin, he informs on two young people who are active in the resistance.

Father Brown starts solving crimes, much to the annoyance of his housekeeper, the police and especially his bishop, who is not amused by a priest playing detective.