This is a Documentary about the River which gave its name to the inhabitants of the city of Rio de Janeiro. The river called Carioca has been the main source of water supply of the city, for two centuries. During the same period, Rio was the Brazilian capital. It guided the growth of this now great Latin American metropolis, but today it is only a large submerged sewage canal that flows into the Bay of Guanabara. The story of this river is the outrageous History of Urban Development in Brazil. Which is told in this film in a ironically humorous, but deep and moving way.