In his past life, Li Zhou was addicted to gambling and heavily in debt, and his beloved Song Anran was forced to death by the village bully He Lei. After rebirth, he returns to the day of the tragedy, relying on fishing memories from his past life to discover a school of large yellow croaker in the offshore waters, quickly paying off his gambling debts. Facing repeated frame-ups and suppression by the He family, he cleverly used sonar to gather fish and live-water preservation tactics to break the deadlock, and set a trap to expose the He family's robbery in the act, finally bringing the village bully to justice. He successively purchased iron-hulled boats and speedboats, opened a new port, and led the villagers to form a fleet to develop deep-sea fishing.