A widowed mother sends her son Grześ, who has just finished high school, to Warsaw to find a well-paid job and help support the family. But he has no more luck than his neighbours in the dilapidated block of flats where the 13-year-old prostitute Dusia has attached herself to him. Grześ, who also has a retarded brother to look after, is tormented by his inability to prove he can get a decent job.