Bai Chu, the only daughter of General Bai, an important official of the court, was granted marriage by the emperor to Prince Chen. However, Bai Chu had always been thinking about her childhood sweetheart who she loved but had been separated from for many years. However, since it was a marriage granted by the emperor, it was difficult to disobey the emperor's order. Bai Chu could only try every means to force Prince Chen to cancel the engagement after entering Prince Chen's mansion. Little did she know that the marriage granted by the emperor was actually deliberately sought by Prince Chen in order to compete with Prince Qi for the position of crown prince and to win over the power of the Bai family. On the wedding night, Prince Qi arranged an assassination, and Prince 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 the killer organization under Prince Qi - Guigu. When Bai Chu was investigating the truth, she was repeatedly protected by a masked man, who advised Bai Chu to leave Guigu. Bai Chu gradually became suspicious, and took advantage of the masked man's unpreparedness to poison him and removed his mask, but under the mask was the face of Prince Chen.