Gu Xueqing unexpectedly finds herself inside a secluded sanatorium. With her keen observation skills, psychological insight, and meticulous reasoning, she gradually uncovers the patients' strange behavior, the institution's cover-ups, and a series of bizarre cases. Through livestreams, she shares her investigations and helps victims find evidence and uncover the truth. During her investigations, she meets the cold and decisive Shen Muyuan. From mutual suspicion to working side by side, they investigate missing-person cases, thefts, and village secrets. Amid countless dangers and hidden conspiracies, they uncover the truth about Gu Xueqing's origins and fight to uphold justice until the very end.