The film tells the grotesque story of a large family living in an extremely poor shantytown of the periphery of Rome. The main protagonist is one-eyed patriarch Giacinto (Manfredi). Four generations of his sons and relatives are cramped together in his shack, managing to get by mainly on thieving and whoring, among other things more or less respectable.
For the loss of his eye, an insurance company has paid Giacinto a large sum. Giacinto refuses to share his money with anyone, and spends little of it on himself, preferring to hide it from his family, which he routinely abuses verbally and physically. Various members of the family unsuccessfully try to steal his money. When Giacinto falls in love with an obese prostitute, brings her home and starts spending his money on her, Giacinto's enraged wife conspires with the rest of the family to poison him. However, Giacinto survives. In a frenzy of anger, he sets fire to his home. To his disappointment, his family survives.
Giacinto then sells the house to a Neapolitan immigrant family. Giacinto's family refuses to let the Neapolitans take over the shack, and in the ensuing fight, the shack collapses. The film ends with Giacinto living in a newly built exceedingly crowded shack with both his mistress and his wife, together with an apparently reconciled family and the newcomers as well.
- Nino Manfredi - Giacinto Mazzatella
- Maria Luisa Santella - Iside
- Francesco Anniballi - Domizio
- Maria Bosco - Gaetana
- Giselda Castrini - Lisetta
- Alfredo D'Ippolito - Plinio
- Giancarlo Fanelli - Paride
- Marina Fasoli - Maria Libera
- Ettore Garofolo - Camillo
- Marco Marsili - Vittoriano
- Franco Merli - Fernando
- Linda Moretti - Matilde
- Luciano Pagliuca - Romolo
- Giuseppe Paravati - Tato
- Silvana Priori - Paride's Wife
- Beryl Cunningham - Baraccata Negra