Yi Eon is a food-loving ordinary young man who works at the palace. One day, one of the secret royal inspectors comes back seriously ill, and therefore, Yi Eon is chosen as the next secret royal inspector. Meanwhile, Jo Yi who wants to get a divorce from her current husband Chu Han needs evidence that he is a gambling addict in order to make it happen. When she asks her best friend Bo Ri to help her, but she tells her a shocking news.

The sudden death of a maiden, and a suspicious magistrate. Even though Yi Eon is not interested in investigating crimes, he could not turn a blind eye to this case. Therefore, he starts to search for evidence at Bo Ri’s tavern. Meanwhile, Jo Yi finds the account book at Bo Ri’s, and she realizes that it belongs to the magistrate of Gaehwa Valley.

Thanks to the help of Yi Eon, Jo Yi finally gets approval for her divorce. Soon after, an assassin shows up at Local Office, and Yi Eon happens to find out about those accused of criminal conspiracies. Meanwhile, Jo Yi leaves Gaehwa Valley to get to Hanyang and ends up staying the night at a shrine.

Yi Eon and Jo Yi run into a ghost. Jo Yi realizes that the ghost bears a striking resemblance to someone she knows. She starts chasing after it and soon discovers the ghost’s secret. Meanwhile, Yi Eon and Jo Yi hear that Soyang Trading Group is riddled with corruption. They infiltrate the group to save the kids suffering under the tyrannical leader, Cha Mal Jong.

Yi Eon protects his people with the sword as the Crown Prince has taught him. As Jo Yi tries to convince Tae Seo and Mal Jong with her sharp observation, Yi Eon is impressed and wants to keep her with him. Meanwhile, Park Seung sends his son, Do Soo, to Tae Seo when he hears about Tae Seo getting involved with a new secret royal inspector.