Wang Dahai, a destitute fisherman in Haikao Village, rescues a little girl named Tuantuan wearing a pearl pendant from huge waves during a stormy night. Tuantuan can hear the voice of the sea, and with her guidance, Wang Dahai finds large yellow croakers, discovers a seabed cold spring, channels water to build ponds to raise live fish, and reaps bountiful catches. Local tyrant Jin Wanshan repeatedly makes troubles—cutting off ice, dumping sewage, and seizing fishing grounds—which Wang Dahai resolves one by one with unyielding grit. Eventually, Jin Wanshan is investigated and penalized for dumping industrial wastewater, Wang Dahai is hired as a "Deep Sea Resource Protection Consultant," and that sea officially opens a new chapter for Wang Dahai's life.