Florence, 1963. One of the few policemen left in the deserted city, Inspector Bordelli spends his days on routine work and his nights tormented by the heat and mosquitoes. Then a telephone call gives him a new sense of purpose: the suspected death of a wealthy signora. Bordelli rushes to her hilltop villa and picks the locks. He finds the old woman apparently killed by an asthma attack -- though her medicine, close by, has been left untouched.