This drama portrays the life of the 19th king of Goguryeo, Hwanwoong, who was sent from the heavens to make the world a better place. He falls in love with Saeoh and gives her the joojak necklace; however, Kajin becomes jealous since Saeoh has given birth to Hwanwoong's son. She takes the baby and throws him off a cliff. Saeoh, thinking that her son had died, is overcome with grief and turns into the black joojak to destroy the world. ...