This drama is a remake of the UK television series “Undercover” that aired on BBC One from 2016-April-3 to 2016-May-15. Han Jung Hyun (Ji Jin Hee) is an agent of National Intelligence Service (South Korea) formerly Agency for National Security Planning, who has been hiding his identity for quite sometime. Choi Yeon Soo (Kim Hyun Joo), a human rights lawyer, becomes the first head of the agency for justice. These main leading characters of the series uncover the truth, pitted against a huge force holding top position. The series tests their relationship as husband and wife when the secret life of Jung Hyun comes to fore.