Gu Beiyue strictly accompanies Yunxi to protect her since she is his master’s daughter. They arrive near the village where the plaque has taken place and a man who has contracted the disease falls in front of them. They question the man about his origins and he tells them that he did not go through Nanjiang. Hearing this, Gu Beiyue doubts him because the plaque was supposedly in Nanjiang and so, Yunxi suspects poison. She tests him with her needle and she was right, he was poisoned. He tells her that a few days after he picked up a stray bottle a few days ago and sniffed it, he started feeling ill. Hearing this, they ask about the bottle’s whereabouts and he tells them that he found it between the capital city and Nanjiang.
Later, LFY arrives at Nanjiang. He has already instructed his men to set up quarantined zones to treat the plague and to contain it so as to not spread it to non-infected people. LFY then finds an opportunity to speak to Minister Sun alone in order to warn him to keep his distance from him since the Emperor must be suspicious about LFY’s relationship with him. They then talk about the plague and how it is suspicious since it came by unnaturally.
Next, we are taken to the Northern Li’s palace where the Crown Prince has arrived and greets his Imperial mother. He then tells his mother about Qishao’s capital crimes and that he must be punished gravely by his Imperial father. The mother then slyly says that he doesn’t have to ask his father but give the order himself, “Your father is severely ill. I’m afraid he doesn’t have much time left”. Seems like the mother planned everything out so that her son will take the throne even though the Emperor would not write a will. Hearing this, the Crown Prince believes that the Emperor plans to pass down his throne to Qishao.
Back to Nanjiang, the physicians and LFY are trying to find a cure for this mysterious plague. However, they are coming up with nothing. Yunxi and Gu Beiyue arrive and LFY asks Yunxi to leave quickly or else she might get sick with the plague. They tell him that they think the plague might be suspicious and Yunxi promptly tests her theory out. She finds out that the people are poisoned instead of suffering from an ordinary plague. LFY then tells her to leave the antidote and quickly leave this place. But when she tells him that she doesn’t have the antidote, he becomes worried about her safety, “Why did you come then?”. However, Yunxi is adamant in staying here to investigate the poison. And so, Gu Beiyue and Yunxi work together to treat the citizens who have fallen ill to the poison and they seem to be getting better.
Back to Northern Li, Yuze arrives to save Qishao from prison. But he tells them that he is not going to escape because if he does, he will become a fugitive and will never be able to see his Imperial father again. His servants tell him that his father is now ill and news of this is being kept under wrap by the Crown Prince and his mother. They also tell him that he will die once his father is dead. And so, they leave the cell and the maids separate from Qishao to divert the soldiers.
Next, LFY goes to see Yunxi to bring her food. She tells him that she is going to stay up all night to research more since she still has to figure out an antidote for the poison. Hearing this, he says that he will stay up with her. The next morning, Yunxi faints and Gu Beiyue tells LFY that Yunxi has contracted the poison. LFY looks after her and doesn’t let go of her hands, “I’ll be with her”.
Meanwhile, Qishao is at the palace to see his father as he secretly gets in after putting the guards to sleep. He gives his father a pill to eat which the Emperor finally regains consciousness, “Thank you for saving me”. Qishao tells him that he will never forgive him for mistreating him and his mother, “Don’t worry, this pill will make you die faster”. The father truly regrets mistreating him and doesn’t get angry at the fact that Qishao is going to make him die quickly. He also gives Qishao his will and explains why he had to mistreat him and his mother, “I was too weak”. Qishao then leaves his father and goes to collect his mother’s ashes to find it gone! The Crown Prince arrives holding Qishao’s mother’s ashes and bullies him into kneeling and kowtowing before him as he threatens him with his mother’s ashes. Qishao then gets his mother’s ashes from the Crown Prince before realising that the Crown Prince has also contracted the plague when he was in Nanjiang before. The Crown Prince then begs Qishao to save him but Qishao refuses.
The Empress of Northern Li is back at the Emperor’s room to get the will. But then he loses consciousness and passes away while coughing. After realising that he is dead, she becomes angry since he has not given her his will to let her son become the Emperor.
Back to Qishao, we note that he is going to save the Crown Prince of Northern Li, but it is not for free. The Crown Prince asks Qishao to state his conditions for saving him since he doesn’t want to owe him anything. But Qishao tells him that he is not selfish like him and that he knows his words can’t be trusted. Nevertheless, Qishao threatens that the Crown Prince must not do anything to harm his life and protect the people of Northern Li or else everyone in the world will know the contents of the will (which states that Qishao is to become the Emperor). He also brings up the plague that many citizens of Northern Li has contracted and that he should not think of working with Concubine Qin. Hearing this, the Crown Prince immediately orders the guards to arrest him. And so, Qishao tells him that this is why he can’t be trusted since he knows that the Crown Prince will act like this. Thus, he also lets him know that his poison has been temporarily relieved and that he can only rely on Qishao to help him stay alive.
Gu Beiyue is working hard in defeating the poison plague but then there are still many people that are becoming infected in safe areas. This is puzzling as they should have already controlled the plague. General Mu tells Gu Beiyue about a village that contracted this plague first and how it is left with dead bodies. And so, Gu Beiyue goes to that village to investigate to find Qishao there, “Gu Beiyue, you also find this village suspicious right?” Qishao then asks Gu Beiyue about Yunxi to find out that she has also been infected. Hearing this, he becomes angry but quickly goes to find the origins of the plague so that she can be saved asap.
They go to a well to find out that the water in there has been poisoned. A man then comes out to kill them but is too weak against Qishao. He angrily tells them that they must be the reason why most of the people in the village are dead since a stranger (like them) came to their village a month ago, walked to the well and dropped something strange into it. He followed the man to but the man pushed him over the cliff. And so, he had to recuperate for a month since he was seriously injured before he could climb up again. And when he did, he found out that his fellow villagers are sick or dead.
Next, LFY is watching over Yunxi and rushes over when she wakes up. He tells her how she has contracted the poison and she apologises for being a burden. But he comforts her and tells her to rest well. Qishao then arrives but Yunxi pushes him away since she still has not forgive him for lying about his identity. Later, Qishao reveals everything and clears up the misunderstanding in front of Yunxi who was pretending to sleep.
Qishao and Gu Beiyue work together to develop a prescription to cure the people and Yunxi. But they are missing a key ingredient: the purple sage. And so, Qishao travels a few days nonstop to see Doctor Han who was known to know where the purple sage is growing. Although getting the purple safe at this time of season is suicide, Qishao is adamant Doctor Han agrees to help him after knowing that Yunxi has contracted the poison. Doctor Han leads Qishao to where the purple safe is and shows how there is a poison barricade surrounding it, making it hard for them to walk in and pluck it out. But Qishao is adamant in getting the purple safe for Yunxi and gets it. However, he soon falls unconscious and Doctor Han had to save Qishao by pulling him out of the poison barricade. Doctor Han saves Qishao and gives him medicine to cure him from that poison. Knowing that he is alright, Qishao immediately sets out to save Yunxi.
Then, Qishao arrives just in time to save Yunxi from death. They make the antidote using the poison sage and feed it to Yunxi. And so, the rest of the infected citizens are also saved…for now. Qishao informs Gu Beiyue that this antidote is only temporarily and there might be another outbreak in a year unless they find this rare plant called Jue Zhong herbs. And so, Qishao is on a mission to find this herb in order to truly save Yunxi.
Qishao later meets up with one of his maid called Zhuyu who was saved by LFY’s subordinate from the soldiers chasing after her. She tells Qishao that she will follow him forever now that they are no longer related to Northern Li but he tells her that he wishes for her to have a normal life since she has a person to love now. And so, LFY’s subordinate tells him that he will take care of Zhuyu.
Later, LFY meets up with Qishao who tells him that this plague was masterminded by someone sinister and asks if he suspects anyone. LFY says that he will investigate this but Qishao says that the person who poisoned the citizens did it with mind to create more poisoned people like LFY. By revealing this secret, Qishao uses this chance to tell LFY to leave Yunxi alone since he will bring trouble to her. And before he leaves, he also tells LFY that the Crown Prince of Norther Li was also infected and is temporarily cured.
Afterwards, LFY makes plans to draw out the mastermind of the poison plague after realising that the mastermind must have a high status since the evidence he got from the ripped out piece of clothing was made from good quality satin, “It is only found in the palace”.
Meanwhile, Yunxi accidentally finds out the divorce scroll which Gu Beiyue was keeping from her. LFY walks in before stopping when he realises that she was reading their divorce scroll. She turns around to find him looking at her but they don’t mention their divorce as they have a careful conversation about the plague. And so she leaves the room but not before saying that this will probably be the last time they will see each other since they will have nothing to do with each other anymore.
ARGHHHHHH! My heart is breaking for them! LFY is so in love with her and she is just as in love with in! But its so disheartening to find out that they can’t be together right now! Why do dramas have to hurt our hearts like this?