The trip to Chipiona, Cadiz (a beautiful place, full of little white villages and wonderful beaches), of three couples who pretend to find the truth under their skins through the exchange of spouses and the loving sex above the moral conventions of their parents, turns out to be a political buddy movie, doubtful and very illuminating the bewilderment of a country. They decide to meet a weekend at the beach to conduct a psycho-dynamic session led by one of them, an alleged psychologist expert in these issues. They talk, undress, lie and then analyze their impressions and feelings with horny tone of the dialogues and a mixture of intellectualism. In one of these exchange of pairs a woman has been reunited with her former lover, now married and with children, and feels that her love for her has risen. She does not give in to her requirements and together they see a train whose metaphorical sense is more than evident.