Rome. Paola Angeli, a young psychiatrist, following her recent separation from her husband Alberto Salvi, a crime reporter, moved to an apartment overlooking a large courtyard, overlooked by a series of other buildings. It is Christmas. The city is becoming depopulated. Even the courtyard that Paola sees from her windows during long sleepless nights seems uninhabited apart from the few remaining tenants. One morning, not far from Paola's condominium, the body of an unidentified blonde girl is found in a dumpster. Alberto investigates the mysterious crime on behalf of his newspaper. Paola has the impression of having seen a blonde girl with a pair of very showy earrings enter building C the previous night. but Romolo, the building's doorman, excludes him because the tenants are all away on holiday.