There is a mysterious sect called Wuyin in the martial arts world. In the sect, Nie Yinniang ranks first in martial arts. Master Miaohui Shenni assigns Nie Yinniang a mission to assassinate the tycoon Liu Changyi. Nie Yinniang completes the mission with ease, but she gets embroiled in a conspiracy that leads to her meeting Sima Sheng'an, the vice minister of the Supreme Court. During the investigation, the two gradually fall for each other, and they work together to solve the conspiracy.