Once a legendary, triple–board-certi fi ed surgeon at one of Seoul ’s top hospitals, Boo Yong-Joo now hides in plain sight at Doldam Hospital , a provincial outpost far from prestige, being called as Kim Sa-Bu (“Teacher Kim”). There, he guides two young doctors who arrive broken in very different ways. Kang Dong-Joo is brilliant but dangerously hungry for success; Yoon Seo-Jung is gifted yet paralyzed by guilt from a past tragedy. Thrown into relentless emergencies, ethical battles, and a system obsessed with hierarchy and reputation, they are forced to confront what kind of doctors they want to become. Under Kim Sa-Bu’s uncompromising mentorship, saving lives becomes inseparable from reclaiming conscience. At Doldam, medicine is stripped bare: messy, painful, and achingly human.