1937 On the eve of the full-scale outbreak of War of Resistance against Japanese Aggression, the National Salvation Association, an anti-Japanese non-governmental organization, under the leadership of underground worker Zhang Ping, planned to steal the national treasure "White Jade Carving Dragon Seal" which was about to spread overseas. The plan failed because of the mysterious murder of Lin Hai, the highest person in charge of the National Salvation Association. As a result, blue water police inspector Yang Ke and Zhang Ping intervened in the investigation of Lin Hai's murder case, and they gradually became good brothers from the beginning. At the same time, I met Lin Hai's sister Lin, who is also a member of the National Salvation Association, and they fell in love. The three men gradually accepted communism and anti-Japanese thoughts after experiencing such thrilling events as confusing detection, Lin being betrayed by traitors and Zhang Ping being rounded up by the national army. In the end, Ke Yang found out the real murderer, but because of the corruption of the national government, the real murderer was at large, and Zhang Ping died heroically. Zhang Ping's death touched Ke Yang a lot, and finally realized that only * * * could save China, so he did not hesitate to join Linxi in the torrent of revolutionary resistance against Japan.