Inside a prestigious university hospital, three unsettling stories begin to converge: a young girl finds a strange object in her grandfather’s room; hospitalized patients begin dying under questionable circumstances; and intern Kang Seok-ho is blamed for fatal medical errors and hauled before a disciplinary committee. What appears at first to be coincidence gradually reveals a closed system of professional rivalry, power, revenge, and calculated deception. Written by a physician, Dangerous Toy uses the realism of hospital hierarchy and medical practice to turn healers into potential predators, asking how easily expertise meant to save lives can become a weapon when ambition overrides ethics.