Kim Moo-Young wakes up to find he has become a zombie with no memories of his past. Witnessing the death of a Detective, he has assumed his identity to try discover the mysteries of his past. Meanwhile, Kong Sun-Ji works as investigative journalist who quits whilst investigating the 'Santa Killer' case. By chance the two are brought together and various circumstances lead to Sun-Ji working at Moo-Young's detective agency as an intern.