During the latter part of the 14th century, King Taejong abolished the Goryeon Dynasty in order to establish Kingdom of Joseon. Some were aware of the deal he made with an evil spirit—which in turn used their power to possess humans who would control and terrorize the world. The king’s sons, Princes Chungnyung and Yangnyeong, are his main opposition, each with a different reason for standing in his way.
(Source: DramaWiki)
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