The story takes place on the eve of the Anti-Japanese War. The young sea cat who makes a living by fortune-telling and begging has an extremely miserable life experience. His parents are from the Wu and Zhao families in Hutou Bay. However, the two families have been enemies for generations because of "fighting yangko" and do not intermarry. The children born to those who dare to have an affair will sink into the sea. In those days, his parents sacrificed themselves to save him, and the sea cat survived by chance. On his way to the rivers and lakes, he reappeared in Hutou Bay, triggering a long-silent chaos, and at the same time formed a deep relationship with the two girls Wu Ruoyun and Zhao Xiangyue. Driven by the tide of the times, the sea cat was introduced by the Communist Party member Wang Tiankai to join the revolutionary team. This man who stood at the forefront of the times eventually influenced the Zhao and Wu families, and became sworn brothers with the pirate Black Shark to fight against the Japanese invaders together. This is a legend of the struggle of an unyielding nation...