In 1930s Shanghai, detective Guan Cen and university student Lu Yizhen, meet during an investigation into a mysterious death at a womenβs dormitory. Two years later, Lu Yizhen becomes one of Shanghaiβs first female police officers, working directly under Guan Cen. Together, they reopen an unresolved child kidnapping case, uncovering hidden truths and confronting the shadows of the past.