Lin Chuan, who went missing thirty years ago, returns from a bronze ancient coffin on the ocean floor, only to find that his son and daughter-in-law have passed away, leaving only his grandson Lin Xiaojia struggling to get by with a broken fishing boat. He assumes an alias to approach his grandson, secretly protecting his safety with immortal arts, and helps him rise up against the oppression of the dock bullies. Under his grandfather's guidance, Lin Xiaojia founds Linhai Fishery, masters the true teachings of the Ocean Imperial Art, and finally uncovers the truth behind his father's murder, brings the enemy Du Wanjiang to justice, completes his revenge, and inherits the Lin family foundation.