Jin Shu, a female coroner disguised as a man, is exposed by Prince Jing, Li Jin, and becomes entangled in the undercurrents of political intrigue in the capital. The two join forces to solve a series of mysterious cases, including the Lin family's illegitimate daughter case and the Fang Qing massacre, tracing clues from marks left on the bodies. They discover that all the evidence points to a shocking miscarriage of justice involving the former crown prince's alleged rebellion six years ago. Li Jin appears carefree but secretly assembles a network of covert guards and informants. Using her extraordinary autopsy skills and meticulous reasoning, Jin Shu pierces the veil of mystery, only to discover that Jin Rong, the young brother she adopted, is actually the crown prince's orphaned son. As twelve mysterious seals gradually emerge, the mastermind, Xu Weiyou, closes in step by step, and an ultimate confrontation spanning life, death, and political intrigue quietly begins.