Post Office Box 1001

Barcelona, Spain. A young man is murdered in the middle of the street in front of the police headquarters. Miguel and Marcial, two agents of the Criminal Brigade in charge of the investigation, find in the victim's room a newspaper where a cryptic classified ad appears.

A Corpse Has Been Killed

A girl dies in a car crash, but the autopsy reveals she was actually poisoned. The police comes up with a scheme: telling the media the girl is alive in a hospital hoping the murderer surfaces. However, nothing is like it seems to be.