Substitute for the Empress

In the Song family of the Yong'an Marquis Mansion, there are two sisters: the legitimate daughter Song Mingyue, born to the main wife, and the concubine-born Song Xingchen, daughter of Li Yin. The two look nine-tenths alike. As they grow up, sister Song Mingyue becomes an Imperial Concubine. Unable to bear children herself, she has Song Xingchen enter the palace as her substitute to receive the Emperor's favor and bear his heir. Song Xingchen feigns refusal but secretly agrees, carrying the jade pendant her mother gave her before dying. She steps into the palace and begins her journey of revenge.