The daughter of a widower, Shen Qingzhu, disguised herself as a man and worked as a jailer in the palace to avenge her father. When she was dealing with the sudden death of a concubine, she found out that the body had been tampered with, and was forced to get involved in a serial murder conspiracy by the palace forces headed by Queen Xiao. Relying on her post-mortem skills and logical reasoning, she cooperated with Lin Zhaozhi, a disciple of Jixia Academy, and gradually uncovered the connections between the "death of the concubine Xian", "the miscarriage of the concubine Shu", and the "poisoning of the prince". In the process, she encountered crises such as frame-up, pursuit, and identity exposure. In the end, she collected evidence to reverse the situation, make the facts of the Queen's Group's crimes known to the public, clear her father's wrong, and end the dark rule of the palace.
