Wudu Gate is a notorious school in the rivers and lakes. the old boss relies on a medicine bath to maintain his old age, with only one disciple Yang de (Jiang Sheng). Feeling that the evil things had been done, the old boss ordered Yang to clean up the door and look for the treasure of his uncle. Yang de's five brothers practice five kinds of martial arts derived from poisonous insects, namely: centipede (Lufeng), snake (Wei Bai), scorpion (Sun Jian), gecko (Guo Chou) and toad (Luo Mang). Pretending to be a beggar, Yang Deqiao found out a county seat and happened to encounter an anonymous uncle and his family being destroyed. The murderer was the eldest brother and the second brother. Although he Qiaotou in this county captured the eldest brother with the help of the fifth brother who practiced toad kung fu, the county magistrate colluded with the second brother to put the fifth brother in prison and killed him. The third brother often meets the second brother at night, taking control of the overall situation behind the scenes. Yang Defa revealed his identity to each other after he caught the head, that is, the fourth brother, and the two decided to work together to eliminate the master brother and the second brother. The third brother in the dark decided to do it.