Six months before his retirement from the criminal police, inspector Joss finds his colleague Gouvion dead, in a poorly faked suicide attempt. Joss loses his temper, and investigates on his own, which leads him through the bas-fond of Paris...
Auguste Maroilleur, an elderly farmer, exploits 400 hectares of crop land with the help of his family, over which he rules with an iron hand. Things go awry the day he discovers one of his grandsons is involved in drug traffic. To make matters worse, the reckless youth has hidden the white powder in the Maroilleur farm. Without a moment's hesitation, Auguste gets rid of the toxic substance but, of course, the mob has different views...
In August 1952, a family of British tourists is found by the roadside in Haute Provence, brutally murdered. In the ensuing, very public, investigation a local landowner, 75 year old Gaston Dominici, is arrested for the murders, having been denounced by his sons. Under police interrogation, Dominici confesses to have killed the family and it looks certain that he will be charged, tried and sentenced to death. But then the case begins to collapse. The old man retracts his confession and the lack of evidence against him becomes apparent…
Whilst being transferred to a psychiatric hospital, a ruthless serial killer Gassot makes a break and goes on the run. He arrives in Marseilles, intending to escape abroad. Here, he falls for a young prostitute, Gerda.
Mr Jo, nicknamed "the man with the Buick", is the darling of the small town of Honfleur. But he is in fact a trafficker with a bad reputation who would like to forget about his past, now limiting himself to smuggling rubies under the cover of a charitable organization which offers underprivileged children holidays in Switzerland. However, Mr. Jo is in love with a pretty widow and, in order to marry her, he is willing to get involved in a hold-up again. And "the man with the Buick", who seemed so honorable, will surprise the inhabitants of Honfleur when Inspector Menard reveals his secret activities.
