Goong S is about a Korean royalty, Lee Hoo who has been raised among commoners. His mother, a former princess escaped the Palace in oder to keep her protect her baby from the bad people among the government who wants the throne. After the throne's successor, her husband, died. The throne was left vacant. A candidate for the throne is one of the bad guy's son. At this time, Lee Hoo was found and brought back to the Palace by the Empress. However, being raised as a commoner, for him to transform into a royalty is no joke. Lee Hoo goes through many challenges and scandals in order to be recognize. He also has to compete with the other throne candidate. However, the problem is, his opponent receive more supports from the people and is better than him in almost all ways....