Chen Zhen went to Japan to learn advanced technology at the command of his disciples, but found that many Chinese men were missing. With the assistance of his friend Liang Shaowen to investigate the real murders behind the scenes, Chen Zhen and the main leader of the Black Dragon Society, Ito Shinji, President Yamada Shinan, and others fought wistfully, and finally disintegrated the conspiracy of the Black Dragon Society, destroying Japan's own laboratory.