During the Joseon Dynasty, the Secret Royal Inspectors are the eyes and ears of the king. They travel the provinces undercover and listen to the plight of the common people, investigating abuses and corruption of government officials. L, Kwon Na-ra, Lee Yi-kyung, Lee Tae-hwan, Jo Soo-min, Ahn Nae-sang, Choi Jong-won Added on Amazon Prime 2023-07-23. Youtube Trailer