The princes gather for drinks in one of the great halls. Having drunk too much, Yin'e rushes out to be sick but is seen by Ruoxi who, to his delight, has arrived bearing a birthday gift, a thousand personally folded paper cranes and also sings 'Happy Birthday to You' for him. Unknown to the both of them, Mingyu also appears and after some heated words with Ruoxi, the two girls start fighting eventually falling into a pond. Fortunately, Yinxiang and Yinti, respectively the thirteenth and the fourteenth princes, arrive to help them from the pond. Ruoxi scolds Mingyu again, leaving her in tears. Her biting words and her furious demeanor earn her the nickname of "Defiant Thirteenth Sister". Ruolan is angered by Ruoxi's behavior and refuses to speak to her for several days.

Since the Mid-Autumn Festival and the announcement of Yin'e's engagement, Ruoxi has been moody. The inability to control one's destiny drove her to melancholy. Yin'e becomes depressed and spends much of his time drinking. Yinti believes that only Ruoxi can break him from this depression. Ruoxi meets Yin'e for the last time and lets him know of her feelings for him. Winter arrives and Ruoxi revels in the crystalline weather, frolicking in the snow when Yinsi joins her. In a moment of awkwardness, she nearly falls but Yinsi catches her hand to steady her, but does not let go. His behavior confuses Ruoxi and she feels a sense of guilt towards her sister. Yin'e's wedding day arrives and both Ruoxi and Ruolan attend, but Ruoxi is taken aside by Yinxiang. In their sadness, the two of them drink to drown their sorrows. After a time, they share their sorrows and it is an unburdened, though drunken, Ruoxi when she returns to her estate.

Yinxiang and Yinti discuss the concept of "equality and freedom", which Yinxiang heard from Ruoxi when she spoke of "the thoughts of modern people". Everyone considers her thoughts as being heretical to the way of life they know. During the horse race, Mingyu performs spectacularly impressing the audience. In a moment of pique, Mingyu angers Ruoxi into mounting up, but to her chagrin Ruolan requests that she be permitted to perform and impresses everyone with her grace. Yinsi later goes to Ruolan, hoping to help her forget her pain so that, as a married couple, they can start anew but is coldly rejected by Ruolan.

Ruoxi and Yinxiang discuss their lack of etiquette on Yin'e's wedding night but discover that it is all a misunderstanding. Yinxiang was not unhappy because of his feelings for Mingyu but on that night but because his mother was giving birth and Ruoxi was not unhappy because of Yin'e. With their misunderstandings cleared, Yinxiang takes Ruoxi to the home of his best friend, Luwu, and the three talks and enjoy each other's company late into the night. When Rouxi returns to her estate, she realizes that it is very late and goes to Ruolan to apologize but happens upon her sister gazing longingly at a portrait. Bit by bit, Ruolan tells of what happened years ago. Yinsi had always loved Ruolan but when they were wed he discovered that her heart belonged to another, her childhood friend from the steppes, Qingshan. In a bid to ensure she marries Yinsi, Ruolan's father sends Qingshan to war where he dies in battle. Ruolan, unable to forgive Yinsi, spends her days with a small Buddha. To help Yinsi see Ruolan as she was in the past, Ruoxi gives a jade bracelet to her sister but Ruolan mistaken believes that the gift is from Yinxiang.

The end of the year arrives and Ruoxi attends The Lantern Festival with Qiaohui. At the festival, they meet Yinxiang who is with Luwu and the four of them go to enjoy some food and drink where they meet Yinti and the other princes. Seeing Ruoxi with Luwu, Yinti feels that Ruoxi is lowering her status and quickly takes her to Yinsi. Yinsi tells her of Ruolan's past, which leaves confused Ruoxi wondering whether he has feelings for her or takes her for her sister's replacement.

Thanks to the efforts of the princes, Ruoxi has not yet been selected as an attendant. Several of the concubines state their desire to have Ruoxi serve them but the empress, not wanting to offend anyone, sends her to be a tea serving girl to the emperor himself. As a rookie, she is cautious but with her modern era smarts she gradually gains the confidence of the emperor and soon appointed as the lead tea server.

The storm over the impeachment of the heir eventually passes and so to gain favor with the emperor, the princes suggest that they accompany the emperor on a trip out of the palace. The emperor commands the Yinsi to remain behind to administer to the affairs of state. In fact, it is a ploy by the heir to reduce the power of Yinsi's faction and to make the prince a scapegoat in the event of anything going awry while the emperor is away. The infighting amongst the brothers becomes increasingly apparent.

Yinzhen brings Ruoxi along for the trip with the emperor, suggesting that she bring some more tea and be careful. As he has to remain behind to administer to the affairs of state, Yinsi forlornly bids Ruoxi farewell. Yinsi finds out that it was Minghui's interference that caused Ruoxi to be unable to serve any of the concubines. As a result, he ignores Minghui who begs his forgiveness and promises never to do anything to displease him again.

Meanwhile, Ruoxi, as part of her tea serving duties, delivers tea to the emperor and the princes in individually selected cups bringing praise from all. Ruoxi then requests that the emperor permit her to learn horse riding, which he happily permits.

Yinxiang meets Mongolian Princess Minmin at the goat roping arena and become friends, but neither knows of the others' birthright. However, that night the emperor orders that a party be held and while performing, Minmin sees Yinxiang, who had introduced himself as "Little Star" at the arena. To her surprise, he speaks to her in Mongolian and an attraction begins to grow between them.

Ruoxi is angered that Yinxiang failed to attend the horse-riding lesson as promised. He had promised to go but had been intercepted on the way by Minmin to go sheep herding. Yinzhen, on his own initiative, took his place as Ruoxi's riding tutor. On seeing him, she tries to leave but is caught by the prince who passionately kisses her.

That night, she goes to find Yinxiang to get an explanation as to why was not there to teach her riding. Yinxiang believes that Ruoxi has feelings for Yinzhen and that he is a passing fancy. Ruoxi, of course, cannot reveal that Yinzhen is to be the next emperor, which is why she so careful around him. Depressed by the situation, she returns to her estate to throw a tantrum.

News of the eighteenth prince Yinxie's worsening illness arrives but the ministers feel that the emperor should concern himself with the affairs of the empire and advise against informing him of the prince's condition. However, Yinsi goes against the consensus and decides to inform him. Upon receiving the news, the emperor decides to decamp and return to the capital in three days.

The crown prince, Yinreng, in a drunken stupor, trespasses into the Mongolian bivouac and is later scolded by the emperor. Yinreng believes that this incident was instigated by his elder brother and goes to demand an explanation from him. During the argument, he is told that it is only a matter of time before the emperor strips him of his title. Furious, Yinreng rushes to the emperor and erupts in a rage, further worsening the emperor's mood and endangering his succession to the throne.

News of Yinreng losing his title rocks the capital and causes the ministers, fearing to side with the wrong prince, to speculate on who may be the new heir. All of them hope that the emperor retracts his command. The third prince, Yinzhi (Prince Cheng), arrives with news. He reports that the recent behavior of Yinreng may have been the work of the eldest prince, Yinzhi (Prince Zhi), and a search of his estate reveals drugs. Enraged, the emperor orders the life imprisonment of the prince. Upon Ruoxi's return to the capital, Yinti delivers a love letter written by Yinsi, which delights and startles her. She goes to Yutan's home to get news and discovers that there are people in the palace hoping to raise Yinsi to be heir. With her foreknowledge of history, she wants to write a letter of warning to Yinsi but knowing that history cannot be changed, she doesn't. Yinreng to beg forgiveness from the emperor and, again, with her foreknowledge Ruoxi knows that the emperor will forgive him but the time was not right.

Another new year arrives; Yinzhen bestows on Ruoxi a gift of a Mulan necklace while Yinsi continues to write love letters, which greatly moves Ruoxi. Yinsi's supporters urge Ruoxi to reveal her discussions with the emperor but are firmly rebuked by Yinsi. Still believing that history is unchangeable, she tells Yinsi in passing that the emperor still loves Yinreng very much. She decides to write him a warning letter, but before she can deliver it to him, she encounters Yinzhen and during their conversation, Yinsi departs the court.

In a bid to help Yinsi, Ruoxi begs the emperor to consider their paternal ties, but the emperor is unmoved. Yinzhen earns the ire of his mother for failing to help Yinxiang when the emperor ordered the punishment. Her anger leaves him deeply unhappy.

Yinsi, saddened by the loss of his rank, seeks Ruolan to lessen his burden but she still treats him coldly. Therefore, he looks for Ruoxi instead but instead encounters Yinzhen and the two princes’ end up having tea together with Ruoxi.

After a time, the turmoil of the Yinreng's loss of rank passes and his rank is restored, the other princes are also promoted and Yinsi is rehabilitated. Soon it is Ruoxi's birthday and Yin'e, in high spirits, wishes to celebrate her birthday but she only wants to see her sister, Ruolan. On her birthday, Ruoxi is sadly resigning herself to never being able to return to the present when she is summoned by one of the imperial concubines. Her summoning was actually organized by Yinsi so Ruoxi could see Ruolan. Upon seeing her younger sister, Ruolan asks if she has someone, she cares for and advises that she prepare for her own future.

Yinti comes to find Ruoxi to chat and directly asks her if she has any feelings for Yinsi. Her evasion eventually angers Yinti but coincidentally Yinzhen and Yinxiang, who have been looking for Shouxing to have tea, appear. Yinzhen bears a gift from Ruoxi's childhood, nail polish.