Haechi - Season 1 Episode 35 The Rights to Become a King
Overview: King Gyeongjong dies of poisoning, and a 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.