Caleidoscope of documentary-like scenes and re-enacted episodes of a day in the life of a large port town – Lisbon, from the old district around Saint George's Castle down to the docks and the 'Sagres' on the Tagus river, to the new commercial districts.
João, a blacksmith in Portugal, lives with his wife, two children and father. After work, he goes to the cabaret, where he meets up with Ana, his mistress. Ana is seduced by a fado singer, provoking João's jealousy.