When fisherman Zhou Jianjun divides the family property, all he receives is Dahuang, a limping spiritual dog. Relying on the dog's treasure-hunting abilities and warnings of maritime dangers, he gradually builds a fleet and a harbor. Despite the greed and schemes of his relatives, he stays true to himself. After discovering a centuries-old shipwreck, he voluntarily reports it to the state and cooperates with archaeologists in recovering its treasures. He leads the villagers toward shared prosperity while protecting the ocean and cultural relics, embodying the ordinary person's profound duty to family and country.