Marin, a middle-aged man, returns to his birthplace. Nearly twenty years has passed since he has left these parts - the mouth of Veleka, to him the most beautiful river on earth. Bay Petko welcomes him. In his memories, Martin meets the friends of his youth, with whom he has carried out the collectivization of farming. He remembers some of their mistakes. Without thinking twice, they had expelled one of the most conscientious communists from the party, Parvan, who had the courage to oppose their ill-advised actions. Wrongly accused of hostility to the revolutionary changes he commits suicide. The wisdom and calm of the eternal river are above the human passions. Even the memories of the hanging down the real enemies, such as the bandit Velev guilty of treason, criminal and political outrages, have begun to fade away. Marin's graying hair and the wrinkles on his face bear witness to his painful inner evolution.