Gil Su Hyeon is extremely intelligent. At the age of 10, he attended Harvard University and after graduating, he went to work at the FBI. 10 years later, he decided to come back to South Korea. He now works as the leader of the Special Missing Persons Unit. The unit deals with about 1% of special missing cases involving violent crimes. His appearance borders on perfection, but he holds a secret. DetectiveOh Dae Yeong joins the Special Missing Persons Unit. He has worked as a detective for 20 years and he has an obsession in observing the law. He is known as a master of missing person cases.