Su Qingyuan, a talented girl from the south of the Yangtze River, rushed to Chang'an because of the wishes of the old lady of the Zhenguo Palace. On the way, he was robbed and was rescued by a mysterious young man in white. When he first entered the Duke's mansion, he encountered a strange environment with hidden complexities. She wants to explore her mother's past, and what kind of entanglement she will have with the young master in white. Everything slowly unfolds under the moonlight in Chang'an.
