Bai Chu, the only daughter of General Bai, an important official in the imperial court, was granted a marriage by the emperor to Prince Chen.But Bai Chu has always been thinking about Xinyue, his childhood sweetheart who has been separated for many years.However, due to the fact that the marriage was granted by the emperor and it was difficult to disobey the emperor's order, Bai Chu could only try every means to force Prince Chen to break off the engagement after entering Prince Chen's palace.Little did they know that the marriage granted by the emperor was actually deliberately obtained by King Chen in order to compete with King Qi for the crown prince position, so he wanted to win over the power of the Bai family.On the wedding night, King Qi arranged for an assassination, and King Chen died tragically. Bai Chu's parents also died in the assassination.Overnight, she lost her love and family affection.She decided to avenge her husband and parents, so she disguised herself and entered Guigu, the killer organization under King Qi. While investigating the truth, Bai Chu was repeatedly protected by a masked man.