King Gyeongjong dies of poisoning and rumor spreads that the Crown Prince let him die intentionally. The Chief Justice blames the Crown Prince and objects to his enthronement. The Crown Prince himself questions himself in self-doubt. But with his former teacher's support, the Crown Prince goes to meet Queen Dowager and take control. 

A mysterious plague spreads across the whole nation within days. As if the epidemic wasn't enough, news that Prince Mil Poong and Wi Byung Ju have escaped from their place of exile shocks the whole palace. Dal Moon just begins to collect information that many wells around the nation has been tasting strange lately.