The story of a princess from a fallen kingdom and the emperor of a new dynasty. Both leads have only ever been with each other.
Jiang Yan, princess of the Jiang Kingdom, is the least favored princess in the palace. Rumor has it that she is not the emperor's daughter, but the illegitimate child of Consort Chen and another man.
The emperor knows nothing of governing and is greedy for beauty. He took the peerlessly beautiful Consort Chen into his palace even though she was already married, and plotted to kill Jiang Yan's birth father. Consort Chen arranged a betrothal for Jiang Yan early on, planning to wed her to Chu Jue, the crown prince of the Chu Kingdom, her own birth family. But before the princess could marry, Jin Yu staged a rebellion and murdered the emperor.
At first, the male lead demotes her to a palace maid and makes life difficult for her at every turn. But as time passes, he gradually falls for her. He also learns that she was the one who saved his life when he was young. He admires how she argues her case when falsely accused and how she refuses to give in. He wants to make her his consort and keep her by his side forever, like a caged songbird. But the heroine refuses. She has never been willing to be confined in a golden cage. She longs for freedom and hopes for a love between two people who will stay together for life. She wants to see more of the world. Later, she follows Chu Jue to the Chu Kingdom. After all kinds of events unfold, Jin Yu and Jiang Yan reconcile, and Jiang Yan falls in love with him as they spend time together.
The second male lead is the shrewd crown prince of the Chu Kingdom. His mother died when he was young, and he was sent to the Jiang Kingdom as a hostage. Later, as power struggles break out within Chu, he returns to his kingdom. He and the heroine grew up together, but she is not the moon in his sky.
Happy ending.