Deep within the imperial palace, in the incense hall, Consort Shu is assaulted by Prince Rong. In the struggle to resist him, an unexpected death occurs. Plotting against an imperial relative is a crime punishable by the extermination of an entire family, leaving the Su clan on the brink of disaster. Xiao Changyin, the powerful eunuch who holds the imperial seal and commands influence throughout the court, witnesses the incident and gains a fatal hold over Consort Shu. With nowhere else to turn, she begs him for help, and the two form an alliance built on calculation and mutual exploitation. Xiao Changyin agrees to cover up the incident on the condition that Consort Shu will serve his interests in the future. Disgusted by the emperor, Consort Shu has no desire to compete for his favor in the harem, yet she is trapped and powerless to escape her fate. Behind the vermilion palace walls, the two constantly test and outmaneuver each other as a deadly game of political intrigue, involving both their lives and their struggle for power, begins.