Lorenza, divorced from her rich husband, has three restless children. She lives listlessly and ends up in a strange relationship with her sister-in-law. In the meantime her 10-year-old eldest son, Massimo somewhat disturbed, kills the youngest son, tortures the housekeeper and eventually kills his little sister. Meanwhile she has joined a revolutionary group of objectors, who by means of violence want to rouse the proletariat from its lethargy. Her son now tries to frame his mother for the death of his brother and sister. But this time the mother reacts, causing her son's death. At this point she starts to prepare explosives for her cause and with satisfaction blows up the factory of her bourgeois ex-husband.