It's all about the diamonds. Their underground cutting is established in a provincial town. The criminal business is controlled by the owner of the local restaurant Pavel Sergeevich - Pavlik. Together with him is his former school friend, police chief Valery Petrovich - Valera. Pavlik is also trying to involve another former classmate, engineer Yuri Vladimirovich - Yu. V. in his business.
The fate of Yu.V. did not work out. He went to prison on false charges. Upon his release, Yuri Vladimirovich happily accepts Pavlik's offer to work in his hometown. But the position of chief engineer turns out to be just bait in the diamond scam.
Yu. V. faces difficult trials and dizzying adventures. All the more dramatic because a woman is involved. This is Rita, the wife of the policeman Valera, whom Yu. V. loves. The intrigue twists even stronger when Yu. V.'s only daughter unexpectedly appears in the city - a student at the capital's university, Masha, whom her father has not seen for many years.
Mysterious disappearances, chases, shootouts, blackmail... In extreme circumstances, those who think more about others than themselves will win.