Lin Shu, a resident physician in emergency medicine, unexpectedly awakens a medical system that allows him to see disease entries appearing above patients' heads. From meningitis and ruptured spleens to heart attacks, Takayasu arteritis, lupus, and air embolisms, he repeatedly saves patients from the brink of death with the help of these diagnostic clues and his exceptional clinical judgment. As his abilities in internal medicine, surgery, and critical care continue to advance, Lin Shu grows rapidly through doubts, misdiagnoses, and life-or-death emergency interventions, embarking on a journey from an ordinary resident to a top-tier physician.