On the night of her wedding, Zhou Tangzhi is secretly drugged by her younger sister, Zhou Tangyue, who takes her place in the wedding dress. Her fiancé, Lu Ci, knows the truth but greedily wants both sisters, forcing Zhou Tangzhi to accept the position of a concubine. She smashes her jade pendant, breaks off the engagement, and cuts ties with her cold-hearted, biased family. Disguised as a man, she leaves home and makes a living copying books. By chance, she meets Emperor Chu Xuanye, who is secretly investigating a case incognito. Impressed by her integrity and courage, he makes her a promise. At the grand Heaven-Worshipping Ceremony, she is officially proclaimed Empress. Three years later, Lu Ci arrives in the capital with Zhou Tangyue. Mistaking Zhou Tangzhi, who has left the palace, for a destitute palace maid, he arrogantly believes he can control her once again. But as the lanterns at the palace banquet light up one by one, he finally sees who stands behind that so-called palace maid.