Jung-ho, the former South Korean undercover hid in North for 20 years. When he finally flees back to South, his dead wife starts to appear and haunts his memory. Tracing back his faint memory he looks for his old colleagues who are supposed to return to South but they’re all missing or dead. 20 years ago Jung-ho got a mission to help North Korean officer and his family to exile to South. However the operation failed and this made him have an irrevocable decision. The secret past that Jung-ho never wants to reveal is about to come out 20 years later in the South.