In a murderously hot June a man’s body is found at the bottom of a flooded sand quarry near Prague. The dead man is sitting in the car that he went down with. It is the police officer Zapletal. The Prague chief inspector, Marian Holina, takes over the case, assisted by a young, inexperienced, but clever colleague. Holina, 47 years old, a Prague native with Slovak-Hungarian roots, is an attentive observer. In his work he is often guided simply by intuition.

It soon becomes clear that there are a lot of suspects. The clues lead to a marijuana grower and his wife; the two were probably blackmailed by the dead police officer. A renowned architect, his young Cuban wife and his daughter also seem to have something to do with the case. A dark secret lurks in the background. The case turns out to be more difficult than initially expected; the two-man team needs reinforcement. Thus the policewoman Lida Sotolova joins them. Her investigative drive is sometimes too much for her male colleagues. And another woman joins in, albeit much more subtly. It is Holina’s girlfriend Sabine (ironically, the wife of one of his colleagues). She is an astrologer and can create horoscopes of the suspects and the dead, which Holina does not dismiss. The results give him something to think about. The investigators laboriously work their way through a thicket of evidence; their work is made even more difficult by the fact that some of the witnesses who could have shed some light on the case die tragically during the investigation. It gradually becomes clear that the policeman’s murder is connected to a past that several of the suspects are trying to cover up—because they are all involved in the case. But only one of them is the murderer.