The episode starts with Queen angrily marching towards servant’s quarter to confront her about poisoning Grand Heir. She confessed that her family was kept hostage and hat she was forced to prick the Grand heir with needle. However, she says that it’s not her who poisoned the Grand Heir. Queen asks her to say who it is and she would make sure to protect her family. The maid confesses that it’s not possible for her as they are much formidable than her and commits suicide. Queen angrily lashes at the kitchen employees for trying to poison the Grand Heir. However, she couldn’t find any clue against the enemies. Crown Princess begs in front of Queen to send her out of palace as she can’t afford to lose her son too. She threatens to commit suicide but Queen confronts her that how could she think of ending her life without protecting her son.
Do wager lashes out at the King for not passing the taekhyeon yet. The King asks whether she would depose the Queen like she did once if he doesn’t. He asks whether she would get him down the throne too if he doesn’t comply. Queen reminds him that it was all startd by him. He recalls asking Do Wager to do something to get himself to the King’s post. Do Wager recalls killing the Crown Prince for the same. She says that she started it all for him and asks him not to forget it. The Grand Princes were worried about the Queen and came with food to enquire about her well being. Queen haves it and acts normal in front of them. They ask if taekhyeon is passed will they get killed like the other Grand Princes before them. Queen promises that she won’t let anything happen to them no matter what. Seong Nam learns that it’s proved that Grand Prince died because of the medicine from outside. He confessed in front of the King that it was brought by him. The King first asks him to first stay away from the matter as he would get killed if he was proven wrong. However, Seong Nam pleads for a chance and King asks him to prove that the medicine is harmless before the trial.
Queen scares for Grand Heir’s safety as they couldn’t get any clue against their enemies. Chief State Counsiller promises Consort Hwang that he would make sure to not let Queen meet Physician Kwon. Do Wager scolds Court Lady Shin for not informing her about Queen meeting deposed Queen Yoon. Court Lady Shin clears that her loyalty lies with Queen and Do wager lets her go for the time being. She heard Do Wager say that she won’t use deposed Queen against the Queen in trial. Queen sets out to meet Physician Kwon only to confirm something. As expected she couldn’t meet the Physician. Consort Hwang meets him in prison and seduces him again to be in her favor. Seong Nam sets out to find Master To Ji but finds him left the plague center. He searches for him while the King waits for Seong Nam to get the proof. The trial commences and its proven that there is no poison in the Crown Prince’s body. Hence it’s claimed that it was the medicine from outside which caused the death. Queen counter argues while the King asks Physician Kwon about who gave the medicine to him. Physician Kwon takes Queen’s name and the Queen accepts. However, the Queen says that it was given to her by Crown Princess and so she trusted it. The servants checked the Crown Princess’s chamber and found the hidden medicine. Crown Princess begs innocence but the proof were against her.
The King commences the court the next day. Seong Nam spots Master To ji but he escapes from his sight. Consort Hwang and Chief State Counsiller were taken aback by the wise move of the Queen and decides to make use of it to both depose the Queen as well as the Grand Heir. At court, the councilors suggest for the same and the King gets angry at their suggestion. They force the King for their decision but he leaves angrily confronting Chief State Councillor. He’s practicing vigorously to vent out his frustration when Seong Nam comes there confronting the King to do something. The King makes it clear that I’s not true that everything is in his hands and feels guilty everytime when Seong Nam unintentionally mentions about “killing own brother”. Queen met with Do Wager and says her about meeting the deposed Queen. She reveals that she knew his secret and to maintain it she asked for help from her. She called Chief State Counsiller and agrees for taekhyeon but with a condition to send Crown Princess and Grand Heir out of the palace as commoners. She also promises to step down from her Queen position if none of the Grand Princes make it through the Crown Prince post. Chief State Counsiller agrees and says Hwang about his plan to kill the Grand Heir once they become commoners.
The King announces that he’s deposing the Crown Princess and Grand Heir as commoners and sends them out of the palace for exile. They both were taken away with hands tied but Seong Nam releases the rope and promises Grand Heir to give back what is his. Physician Kwon also leaves while Chief State Counsiller’s men wait for killing Grand Heir. However they get shocked when they find the cart empty. Crown Princess and Grand Heir reach the place where the Queen was present. The Queen recalls convincing the Crown Princess to take the blame so that she could protect the Grand Heir. She also recalls Seong Nam angrily confronting her regarding making the Crown Princess a scapegoat. Queen asks him to take the Crown Prince post to protect the family.
Seong Nam immediately agrees and swears to get the right for Grand Prince. Physician Kwon left an apology note for Queen who asks her people to investigate about him. Kwon meets with Master To ji. Queen meets with King who doesn’t want someone to be elected as King unfairly like him. Queen reminds his promise to not serve the Royal council but the people. She asks him to bring back the real meaning of taekhyeon which is to select the right person for Crown Prince. She requests fair judgement from him. Bo Gum returns the book Do Wager gave and asks her to make him what the current King is. King announces that taekhyeon will happen but it would be only him who would select the Crown Prince. All the Princes get kidnapped for a contest to prove themselves shedding their rights as Prince. Everyone compete in a race.