11-year-old Rosetta and 9-year old Luciano live with their mother in the housing projects of Milan. Internal migration from Sicily, they face prejudice in their adopted city. Their mother is unemployed and their father has long since abandoned them. For the past two years, the mother has hired her daughter out as a prostitute. The authorities raid the place and arrest the mother and a client. The children are destined to be sent to a Catholic orphanage in Civitavecchia, Rome. Two carabinieri, the rookie Antonio and an older man named Grignani are assigned the thankless task of escorting the children there by train. Grignani bails on Antonio at Bologna, leaving Antonio to complete the task alone.