[3] Set in the era of Joseon dynasty the series revolves around Sung Yi-gyum (Kim Myung-soo), a state examination top scorer who works in the administrative and research department of the government office.

He is caught gambling and as punishment, he is reassigned to a new position as a secret royal inspector to investigate the corrupt practices of public officers.

Yi-gyum carries out his new job with the help of Hong Da-in (Kwon Nara), a female inspector, and Park Chun-sam (Lee Yi-kyung), his talkative but affectionate servant.

[6][8] The broadcast was initially scheduled to be premiered on November 2, 2020, but due to re-proliferation of COVID-19, the production was delayed.

[9] The still photos in the period costume, from the set of series were released by KBS as the filming progressed.