At eight years old, Song Zhiwei has her household registration split by her biological father and is abandoned and exiled as a disaster registration, holding only half a burnt household certificate, investigating disaster relief corruption cases with her partner Shen Zhi. In times of crisis, she is rescued by Xiao Chengyuan, the Prince of Jingchuan. She possesses the special ability to transfer others' pain to herself, but it rebounds onto herself. The Prince and Princess of Jingchuan take in and protect Zhiwei, teaching her to read maps and audit accounts, and to understand how to refuse self-sacrifice. Following evidence such as household certificates, granary tallies, and medicinal wax, everyone step by step uncovers the conspiracy of the second prince's faction taking advantage of disaster relief for corruption and adulterating embankment materials.