Legend has it that more than 2,000 years ago, the Kingdom of Nangnang possessed a mystical Ja Myung Drum which will sound by itself when enemies invade. In reality, Ja Myung Go does not represent the drum but instead, is embodied by the King’s daughter, Princess Ja Myung.
Princess Ja Myung and Princess Nak Rang are born on the same day and time to the same father but different mothers. It ispredicted that one princess will become the nation’s saviour while the other will bring the entire nation down. Using her family’s powerful background, Princess Nak Rang’s mother successfully establishes her daughter as the savior princess while Princess Ja Myung, who is branded the princess of destruction, escapes death with the help of her mother and grows up among the common folk.
(Source: DramaWiki)
~~ Based on the Korean legend “Prince Hodong and the Princess of Nakrang” (호동왕자와 낙랑공주).