The series "Goemul" is a Korean detective story about the hunt for a cunning and sophisticated serial killer. Investigator Lee Dong-sik is disillusioned with his profession and is transferred from a major police department to a quiet town where nothing ever happens. His partner turns out to be a young and arrogant police officer named Han Ji-won, whose father holds a high position. But it turns out that even in this backwater town, crimes occasionally occur. Terrifying murders begin to take place in the city.