Chief of the Copacabana precinct Espinosa is more than happy to interrupt his paperwork when a terrified young man arrives at the station with a bizarre story. A psychic has predicted that he will commit a murder - the prediction has become fact in the young man's mind. It's a case more appropriate for a psychiatrist or philosopher, but, rising to the challenge as usual, Espinosa slowly enters the web of a psychologically conflicted man. As the weather changes and the southwesterly wind - always a sign of dramatic change - starts up, what at first seems like paranoia becomes brutal reality. Two violent murders occur and their only link is the lonely, clever man who, only a few days earlier, sort Espinosa's help.