It is two o'clock in the morning. On the radio in Madrid begins one more night "known strangers", a program followed by a big and loyal audience which is made up of students, night workers, or simply, people who can't sleep. One caller confesses his necrophilia tendencies, which was used by a co-worker in order to blackmail him. A student wants to finally try to abandon the call girl job, with which she finances her education and a gang of youngsters decide to do something about the violent husband of a neighbor, while a young writer is searching for a woman, who will mysteriously safe his live in the end. These stories are woven together with bits and pieces from the radio show "Known Strangers", a program followed by a big and loyal audience of people who can't sleep at night.