In episode 9 of "Perfect Crown," the storyline unfolds as Hui-ju and Prince Yi-an's contractual marriage becomes public knowledge. Prince Yi-an grabs Hui-ju's hand and escorts her out of the room, where they meet Jeong-woo, who has just arrived at the school. Jeong-woo advises them to leave first, but they are met with the news that the place is swamped with media.
Hye-jung and Choi-hyun, concerned about the situation, report that the media are everywhere. While Prince Yi-an suggests leaving first, Hui-ju insists they should leave together. In a clever move, Hye-jung and Choi-hyun secretly pose as the royal couple and divert the media's attention by taking the royal car. Once inside, they realize they are holding hands.
At the palace, they refuse to tell Yi-rang where the royal couple is. Meanwhile, Hui-ju and Prince Yi-an are still holding hands in Jeong-woo's office. Public criticism has reached an all-time high as media speculation intensifies.
Jeing-woo, still harboring feelings of jealousy after witnessing the royal couple comfort each other, advises them to keep quiet until the public criticism dies down. However, Prince Yi-an is against this and wants to confess to the public that they are no longer faking their feelings. This confession takes Hui-ju by surprise, but she remains silent.
Jeong-woo insists that optically, it won't make a difference how Prince Yi-an explains things. A staff member runs in and asks Jeong-woo to come see the latest news. Tae-joon is also worried about the news, while Da-young is more concerned about Hui-ju.
To make matters worse, new speculation tries to insinuate that Hui-ju has been receiving special favors from the palace. They accuse Prince Yi-an of stepping in to stop her from being investigated for the palace fire.
Back at Jeong-woo's office, Hui-ju admits that she is scared that her lack of honor will ruin Prince Yi-an. He, in turn, is scared that his honor will hurt her. Jeong-woo returns and asks them to head back to the palace, where there will be a protest at the palace gates the next morning.
Yi-rang beckons Court Lady Lim to prepare for the Council Hall and summons her father. Upon Prince Yi-an's arrival, Hye-jung urges him to proceed to the Council Hall, where Yi-rang has convened the Office of the Royal Families. Hui-ju follows suit, only to be publicly belittled and lambasted by Yi-rang in front of the royal family members. She blames them for tarnishing the royal family's honor. Prince Yi-an is about to erupt, but Hui-ju silently nudges him not to. Frustrated, he clenched his fists so tightly that he bruised himself. After her theatrical outburst, Yi-rang asks Hye-jung and Cho-hyun to escort their superiors out of the room.
In their chambers, Hui-ju tends to Prince Yi-an's bruised hands with concern. He pulls her in for a comforting embrace. The next morning, Hye-jung is taken aback by the chilly reception she receives at the palace. Choi-yhun catches up with her and drops another bombshell. Apparently, whispers are questioning whether Hui-ju faked the incident at her wedding.
Outside, protests rage with people calling for Prince Yi-an to step down from his regency. Jeong-woo makes his way to the palace. He meets with Prince Yi-an to ask him to bear the fall alone. He claims that he is trying to protect the crown and the nation.
He also urges Prince Yi-an to disavow his intention to ascend the throne. The prince inquires what will happen if he refuses to do so. Jeong-woo responds that they cannot have a king without public support; therefore, he would ask Prince Yi-an to relinquish his regency. Prince Yi-an is somewhat taken aback by his response.
We flash back to five days before the leak, when A-reum visited Jeong-woo's office. It turns out that she was there to confess her crimes. Her brother needed surgery, so she agreed to secretly work for Sung-won. She had no idea that the medicine she rubbed on his drinking goblet was intended to kill him.
Surprisingly, Jeong-woo verifies her statement and goes to meet with Yi-rang. She is shocked by the compelling evidence against her father. She asks for time, just as Prince Yi-an arrives to discuss replacing the maids. He gives her until later that night to get her ducks in a row.
Prince Yi-an wonders if she is unwell because she seems stressed. She blames it on the stress of Hui-ju's attempted murder and the changes that Prince Yi-an wants to implement. Elsewhere, Jeong-woo runs into Hui-ju on his way out of the palace. She invites him for a stroll, and he accepts. Obviously, he is concerned about her health and wants to ensure she is okay.
She asks about the investigation, and he points out that it seems she has feelings for Prince Yi-an. She denies the accusation, saying that it would be odd if she didn't show concern for him. How will they deceive the nation if they can't deceive the royal staff? He responds by asking if she is trying to deceive him too.
A subordinate summons Jeong-woo to inform him that the King is about to give his witness testimony. Jeong-woo leaves in a hurry. That night, Yi-rang confronts her father at his place with Jeong-woo's evidence. He doesn't deny the extent to which he went to secure the throne for his grandson. She is appalled, but he reminds her about the fire that took the king's life. She insists that although she lit the fire to burn the royal edict, she didn't kill the king. Sung-won questions who would believe her if everything came to light. According to him, Prince Yi-an must die.
After the visit, Yi-rang runs into Hui-ju at the palace and warns her to tread carefully. Later, she calls Jeong-woo just as Hui-ju is trying to reach him. We have no idea which call Jeong-woo picks up.
The next day, Yi-rang confronts Jeong-woo when he is visiting his father's grave. She questions how he feels being the son of the greatest prime minister. Scoffing, he asks how it feels to be the daughter of the most dangerous lord. Yi-rang clarifies that she won't let that be her father's legacy.
She strikes a deal with Jeong-woo to save Hui-ju, promising to bring down Prince Yi-an by launching a smear campaign against him once the contract is made public. She cleverly manipulates Jeong-woo's feelings for Hui-ju, knowing full well that he desires her for himself. She tells him that they cannot deny the royal couple's love and that to achieve their shared goals, they must work together. She gives him until nightfall to figure it out.
Jeong-woo makes his choice, joining Yi-rang at his father's gravesite and leaving behind the rosary he always carries with him. We return to the present, where Prince Yi-an and Jeong-woo are still in a heated meeting, three hours in. Prince Yi-an reminds Jeong-woo that he has no intention of harming the crown, and both refuse to give up.
Hui-ju hears about Jeong-woo asking Prince Yi-an to step down from his regency just as Yi-rang summons her. In the meeting, Yi-rang blames her for ruining the prince's reputation. Hui-ju stands defiant in front of her, but internally, she wonders if it might be true.
On the other end, Jeong-woo and Prince Yi-an finish their meeting. Hye-jung informs the prince that Sung-won is meeting with the king to officially appeal for the end of his regency.
Prince Yi-an finds Sung-won threatening the king when he refuses to sign the appeal. He grabs Sung-won by his collar and orders Court Lady Lim to take the king away. He chokes Sung-won, asking if he thinks he is unaware of all his scheming. Hui-ju arrives to find Sung-won red as a tomato, struggling to breathe. She begs Prince Yi-an to let the man go. He does, after warning him never to threaten his nephew again. He promises Sung-won a painful death if he disobeys that order.
With that settled, Prince Yi-an goes to comfort his nephew and asks him to come to him when he is scared. Through a flashback, we go back to the night when the king died. Prince Yi-an was there to see his brother but was asked to wait, as he was with Yi-rang.
To pass the time, Prince Yi-an went to play with his nephew and overheard the entire conversation between them. Yi-yoon got scared, so he hugged him and blocked his ears. Presently, Hui-ju walks in on Prince Yi-an comforting King Yi-hoon and is moved. When he apologizes later for what happened with Sung-won, she tells him that he did well. She reminds him that one must fight when protecting the people they love.
That night, as Prince Yi-an was plagued by a nightmare, she silently caressed his head, admitting her fear of ruining him. Meanwhile, Choi-hyun and Hye-jung continued to draw closer, exchanging tips about their bosses. When Choi-hyun changed the subject to inquire about her likes, she seemed flustered.
The next morning, Hui-ju received a call from Tae-joon informing her that prosecutors were investigating Castle Group. She lied that she was going to see her dad, who was feeling unwell. She refused Prince Yi-an's offer to escort her, insisting he attend the palace court. Once he and Hye-jung left, she ordered Choi-hyun to get her a car. She drove to Jeong-woo's office and begged him to save Prince Yi-an, promising to do whatever it takes. He was shocked by her blatant display of feelings.
It finally dawned on Hui-ju that she actually liked Prince Yi-an. She admitted it to Jeong-woo, who said it was unfortunate. Hui-ju went to her dad and knelt before him to apologize. Her humility shocked all her family members. She begged her dad to help her for once in her life.
At the palace, Hye-jung prepared tea for Prince Yi-an to comfort him before breaking more bad news. Apparently, Jeong-woo had requested that Prince Yi-an cease his royal duties. He received a message from Hui-ju saying she was on her way. He asked Hye-jung to keep the latest news from his wife.
The episode ends with Hui-ju running to hug Prince Yi-an, taking him by surprise. He asked why she was gifting him with a hug. With tears in her eyes, she asked him for a divorce.
The epilogue takes us back to the moment when Hui-ju begged her dad for help. She claimed that she could save herself but needed him to save the prince. The statement once again shocked her family.
