Episode Summary
After Song Yiting finds the Moon-Slaying Saber, she demands a three-day trial courtship with "Li Shiliu" (a disguised Shangguan He) in exchange for its return. Meanwhile, her sister Song Yimeng, fearing a shared destiny with her sister and danger from court politics, feigns illness to become Nan Heng's attendant to monitor him. Nan Heng sees through her act but plays along, all while facing pressure from Gao Changyin to abandon Yimeng for Yiting to secure his claim as crown prince—a demand he refuses. Shangguan He's attempts to drive Yiting away fail, leading him to realize he has hurt her genuine feelings. The episode concludes with Nan Heng discovering that the saber has been missing all along.
Spoiler Alert
A Dream within a Dream: Episode 20 Spoilers
The episode kicks off with Song Yiting discovering the Zhanyue Blade. She leaves a note for Li Shiliu to meet her, but Shangguan He arrives in his place, claiming Li Shiliu was busy. Unimpressed, Yiting threatens to expose Shangguan He to Chu Guihong and tells him to stay away.
Worried he won't retrieve the saber for Nan Heng, Shangguan He is forced to disguise himself as Li Shiliu and meet with Yiting. Her demeanor instantly softens. When he asks for the saber, she proposes a deal: she'll give it back if he spends three days getting to know her. If they get along, he must officially propose marriage.
Meanwhile, Song Yimeng is tormented by Gao Changyin's words, fearing she and her sister will end up sharing a husband. Determined to change her fate and protect Yiting, she decides to act. She goes to Gao Changrong, badmouthing Nan Heng and feigning heartbreak and illness to win sympathy. Her goal is to become Nan Heng's personal attendant to keep an eye on him. Though her handmaiden Yingqiu finds her acting unconvincing, Gao Changrong, believing Yimeng is genuinely smitten with Nan Heng, grants her request.
Nan Heng immediately sees through Yimeng's ruse but decides to play along, giving her the chance to "serve" him. Overjoyed, Yimeng impulsively kisses his hand, a moment that lingers in Nan Heng's mind. He instructs his attendant, Fugui, to watch her but also cater to her needs. Yimeng, suspecting Nan Heng will try to seduce her sister, begins searching his study for love letters.
The political situation intensifies as Gao Changyin pressures Nan Heng to secure his position as crown prince. Gao Changyin argues that marrying a daughter of the Song family is the key and urges Nan Heng to marry Yiting instead of Yimeng. When Nan Heng flatly refuses, Gao Changyin begins to consider eliminating Song Yimeng.
Later, while snooping, Yimeng accidentally triggers a secret compartment. Nan Heng stops her before she can see what's inside. After she flees, he opens the box, revealing the mask she had once given him.
In an attempt to scare Song Yiting off, Shangguan He takes her to a gambling den and even puts her up as a stake. The plan backfires spectacularly when Yiting not only wins over the crowd with her skill but also exposes his setup. The next day, he tries to act cheap and insults a new outfit she's wearing, causing her to leave in anger. He later learns from a shopkeeper that Yiting had commissioned the clothes a fortnight ago, specifically for her meeting with "Li Shiliu."
Yimeng's schemes continue as she tries to make Nan Heng drink a potion to curb his desires. He foils her plan by pulling her onto his lap to feed him the medicine, then "accidentally" knocking the bowl to the floor. As a dejected Shangguan He drinks alone, realizing he has genuinely hurt Yiting, Nan Heng overhears him talking with his friends and finally learns that the Moon-Slaying Saber was lost.
