Substitute.

Bai Chu, the daughter of a high-ranking general, is forced by the emperor to marry Prince Chen, despite longing for her lost childhood love. Unbeknownst to her, the marriage is part of Prince Chen’s plan to gain her family’s influence in his rivalry with Prince Qi. On their wedding night, an assassination plot by Prince Qi results in the deaths of Prince Chen and Bai Chu’s parents. Seeking revenge, Bai Chu infiltrates an assassin group under Prince Qi’s control, where a mysterious masked man repeatedly protects her.