Adaptation of 'Prince Serebrenni' by A. K. Tolstoy.

An old man in need of care and attention moves to his son in the city. But soon the son and his wife send the old man to a shelter for the elderly. However, the grandson, who loved his grandfather and understood the cruelty of what is happening, leaves his parents and takes the old man to his future wife.

A group of Soviet counterintelligence officers manage to neutralize spies sent to the territory of the country to obtain secret information about the construction of a large military-industrial complex in Priozersk.