After modern office worker Zhu Xiangxiang dies from working late into the night, she unexpectedly wakes up as a lowly palace maid in the Great Yin imperial palace, with a "Merit System" in hand. There she runs into Emperor Yuanqing, Li Chengqian, who can read minds. He hears every thought she has, from grumbling that his imperial robes are heavy to sniping at her legitimate elder sister, Zhu Lingyue.
To earn enough merit to exchange for her "freedom," Zhu Xiangxiang decides to make the most of her mind-reading power. Right in front of the emperor, her very own "walking thought receiver," she starts dispensing modern knowledge in all sorts of ways. First, she uses the System to trigger a "thunder sound simulator" and scare her overbearing elder sister. Then she offers a secret formula for improving firearms, rising in one leap from palace maid to an official in the Qianqing Palace. Seeing that the emperor diligently serves the people, she also introduces sweet potato and cotton cultivation techniques to solve the people's problems with food and clothing. She even debates the scholars in court and earns the title of "Imperial Preceptor" through her concrete achievements, gaining the honor of outranking officials by three grades.
She helps the emperor improve firearms and repel the English fleet, compiles a "Pandemic Prevention Handbook" to quell an epidemic in Jiangnan, reforms the Imperial College by adding practical subjects, resolves a marriage alliance crisis with the Uyghurs, promotes border trade, and even leads a team to help Siam spread agricultural techniques. All along, she racks up merit with her "spoiler-like" inner thoughts and modern wisdom. Yet she never expected that the emperor, who always quietly supported her and remembered her preferences, had already gone from an "audience to her thoughts" to someone who had fallen for her.
When her merit points far exceed what she needs for "freedom," she looks at the prosperous realm she helped build with her own hands and at the tenderness Li Chengqian can no longer hide in his eyes. Zhu Xiangxiang suddenly understands: compared with returning to the modern world, staying in this warm-hearted Great Yin and protecting the lights of countless homes alongside the person she cares about is what it truly means to have "earned perfect merit."
Zhu Xiangxiang, a modern social animal, uses his merit system to transform himself into a humiliated palace maid. He unexpectedly discovers that the emperor can read her own voice, so he uses his mind-reading skills to reveal the secret recipe for firearms while complaining. She makes inventions, promotes farming, and earns merits. It's lighthearted, funny, and passionate. Let's see how she handles the emperor and plays with the court!