In the middle of the Ming Dynasty, eunuchs were in power. Yu Qian, the Minister of War, was framed and imprisoned. His entire family was executed, leaving only one son and one daughter to be sent to Longmen in the frontier as exiles. Cao Shaoqin (played by Bai Ying), the eunuch of the East Factory, wanted to cut the grass and root out the roots, so he sent people to kill the two children, but was stopped by Zhu Ji, an old subordinate of Yu Qian. Cao Shaoqin also sent his confidants Pi Shaotang (played by Miao Tian) and Mao Zongxian (played by Han Yingjie) to Longmen Inn, where they had to pass through the customs to intercept. At that time, the righteous man Xiao Shaoyan (played by Shi Jun) also rushed to the inn to meet with the inn owner to discuss rescuing Zhongliang. After that, Zhu Ji and his sister Zhu Hui (played by Shangguan Lingfeng), who was dressed as a man, also rushed to the inn. The three groups met, with their own purposes, and tested each other's identities. It soon turned into a melee. At this time, Cao Shaoqin was also rushing to Longmen Inn. He was extremely skilled in martial arts and was the last enemy of the righteous men...