Episode Summary
Jiang Yi is falsely accused and nearly assaulted, thanks to a complex plot orchestrated by Qing'er and possibly Zhu Ziyu. Jiang Si and Yu Qi work to uncover the truth and clear Jiang Yi's name, revealing a conspiracy involving social climbing, betrayal, and a secret noblewoman. The episode is filled with dramatic twists, focusing on the themes of deception and family loyalty.

Spoiler Alert
Episode 18 of "Si Jin" is packed with drama, betrayal, and close calls. The episode opens with Jiang Yi facing the wrath of Madam Zhu, who is determined to make her life miserable. No matter how much Jiang Yi tries to explain herself, Madam Zhu refuses to listen. Just when things look their worst, Zhu Ziyu steps in to defend Jiang Yi, taking full responsibility for the situation. Jiang Yi is deeply touched by his actions. However, the relief is short-lived as news arrives that the Caiyun Troupe, scheduled to perform, is in trouble. The troupe's two stars, Yan Niang and Fei Niang, have had a falling out. Yan Niang's face is swollen after using a product supposedly given to Fei Niang, leading to accusations of sabotage.
Jiang Si questions Meng Nan about the purchase of the rouge, specifically whether the lipstick was ever out of sight. Meng Nan reveals that he was briefly away during the performance. With Yan Niang unable to perform, Jiang Si bravely steps up to take her place.
The evening's performance begins, and while the audience praises the Zhu family, Old Madam Zhu shamelessly takes all the credit. Someone in the audience calls her out, pointing out that Jiang Yi was the organizer, leaving the Old Madame embarrassed and silent.
As Jiang Yi enjoys the moment, Qing'er arrives with alarming news: Jiang Yi's daughter, Yanyan, is missing. Jiang Yi frantically searches for her daughter. Adding to the chaos, news breaks that Fei Niang has sprained her ankle and can't perform the crucial water ritual, a highlight of the entire performance. Just as everyone panics, Qing'er surprisingly announces that she can perform the dance.
Qing'er's performance is a sensation, captivating the audience. However, Jiang Si finds the series of events too coincidental: first Yan Niang, then Fei Niang, and now Qing'er conveniently knows the dance. Yu Qi and Jiang Si deduce that Qing'er's real target was Fei Niang, all along, and that this was a calculated move to shine in front of everyone.
Jiang Si notices her sister is missing and finds her across the river. Jiang Yi is still desperately searching for her daughter. Jiang Si realizes something is terribly wrong. If Qing'er's plan had succeeded, why would she keep Jiang Yi away? Jiang Si suspects someone is trying to harm her sister and rushes to find her.
Jiang Yi suddenly faints. Jiang Si arrives just as Meng Nan is about to take advantage of the unconscious Jiang Yi. Jiang Si knocks him out and hides him. However, Madam Zhu and Zhu Ziyu arrive and discover Meng Nan. They immediately suspect an affair between Meng Nan and Jiang Yi, refusing to believe Jiang Yi's denials. Fei Niang steps forward, falsely admitting to a rendezvous with Jiang Yi, but Zhu Ziyu remains unconvinced. When Meng Nan regains consciousness, he claims he was there to meet Jiang Yi.
Jiang Yi realizes Qing'er has set her up. However, when confronted, Qing'er denies everything, claiming she was busy dancing and couldn't have lured Jiang Yi there. Jiang Si defends Jiang Yi and threatens to report Qing'er to the authorities, but the Zhu family resists. Zhu Ziyu, still convinced of Jiang Yi's infidelity, uses Qing'er's supposed inability to be in two places at once as an excuse and refuses to involve the authorities.
Suddenly, Yu Qi brings in Yu'er, Qing'er's sister, who bears a striking resemblance to her. This revelation clears Jiang Yi's name.
Fei Niang shares a clue with Jiang Si, revealing that she had also realized she was the target and had stepped in to protect Jiang Si. Meng Nan is banished from the Caiyun Troupe. Jiang Si suspects Zhu Ziyu might be behind everything, but Jiang Yi, though aware of the truth, remains silent to protect her daughter, not wanting to escalate the situation.
Yu Qi discovers that Zhu Ziyu has been secretly meeting with a noblewoman. Jiang Si suspects Zhu Ziyu is trying to climb the social ladder by framing Jiang Yi to make way for a new wife from a prominent family. Adding fuel to the fire, news breaks that Meng Nan is spreading rumors about an affair with Jiang Yi, further damaging her reputation.
Jiang Si believes Meng Nan is connected to the noblewoman and tries to get information from Qing'er, learning that Qing'er acted to help her sister, Yu'er. However, Jiang Si doesn't realize their conversation is being overheard. Zhu Ziyu tests his mother's opinion about divorcing Jiang Yi, but Madam Zhu finds no fault with Jiang Yi and is unwilling to agree.