The film takes place over the course of a single night: the longest night of the year, between December 21 and 22 (the winter solstice), when the sun sets around 4:30 p.m. and rises the next day at 7:30 a.m. A long night in which the stories, destinies, anxieties, and dramas of a provincial town in the south (Potenza) intertwine, even if only briefly. Fifteen hours of uninterrupted darkness in which human destiny becomes exceptional, as the night causes the anchors of the day to be lost and four personal stories suddenly accelerate.

In 1944, American sailor Dean Barry arrives in Naples, a city destroyed by bombing after the liberation of Italy. Dean meets Lucia, a young and very poor girl with whom he falls madly in love. Two years later, at the end of his service, Dean has to return to New Jersey and Lucia remains in Naples, alone and pregnant.

A gang of teenage boys stalk the streets of Naples armed with hand guns and AK-47s to do their mob bosses' bidding – until they decide to be the bosses themselves.