Episode Summary
Jiang Si uses Princess Fuqing's Gu-induced blindness to expose a spy in the palace, revealing her Saintess identity to command the removal of the Gu. Zhen Heng's feelings for Fuqing are revealed, while Jiang Zhan confides in Lu Chuchu about his mother's poisoning. The Grand Princess remains unconcerned by Jiang Si's investigation.
Spoiler Alert
The Imperial Observatory's Master Yang reports to the Grand Princess that Yu Qi, while investigating a case, inexplicably dug up a jar of wine buried under a tree. Yang, despite his years at the Observatory, was unaware of the hidden jar, raising concerns that it might contain crucial evidence. The Grand Princess dismisses this, believing all evidence from the past was destroyed. Meanwhile, Princess Fuqing is anxious about a new tutor her mother arranged. Her anxiety turns to delight when the tutor is revealed to be Zhen Heng, a man she clearly admires.
Jiang Zhan, tormented by his inability to avenge his mother, throws himself into work, even ignoring an injured hand. Lu Chuchu, concerned, questions him, but Jiang Zhan, bound by a promise to his father, remains silent. However, at a riverside retreat, he confides in Lu Chuchu, revealing his mother's poisoning. Lu Chuchu pledges her support, but Jiang Zhan, protective, wants to shield her from danger.
Yu Qi and Jiang Si visit the Empress, where Jiang Si notices a flower arrangement identical to her own from a previous banquet. Princess Fuqing arrives, and Jiang Si, observing the princess's blindness, inquires about its cause. Seizing an opportunity, Jiang Si requests to stay with the Empress for three days to learn etiquette. Fuqing objects, fearing conflict with the notoriously arrogant Consort Xian, Yu Qi's intended. However, the Empress grants Jiang Si's request. Yu Qi later questions Jiang Si's impulsive decision. She reveals her suspicion that Princess Fuqing's blindness is caused by a Southern Wu '蛊' (Gu insect), and she intends to use Fuqing's condition to expose a hidden spy in the palace. The Empress, heartbroken by her daughter's affliction and bewildered by the attack, agrees to let Jiang Si help find the culprit. The Grand Princess, learning of Jiang Si's stay at the Empress's palace, suspects Jiang Si is seeking the Empress's protection but remains unconcerned.
The Emperor summons Zhen Heng to assess his feelings for Fuqing, intending a potential match. Zhen Heng praises Fuqing, but not to the Emperor's satisfaction, who wants to see genuine affection. When Fuqing nearly falls while flying a kite, Zhen Heng's instinctive concern reveals his true feelings. However, Zhen Heng, mindful of Fuqing's royal status, suppresses his affection. That night, Fuqing has a nightmare, screaming about a secret related to the Grand Princess, which Jiang Si witnesses.
Yu Qi and Jiang Si notice suspicious behavior from Madam Hua, a palace attendant. Yu Qi brings Madam Hua to his residence under a pretext, only to realize they have the wrong person. The real Southern Wu spy is Madam Duo. Back at the palace, Madam Duo, her identity exposed, attempts to kill Jiang Si. Jiang Si, however, reveals her Saintess (Holy Maiden) totem and orders Madam Duo to remove the Gu insect from Princess Fuqing.
Jiang Si extracts the Gu, but it's a named Gu, deeply embedded in Fuqing for years and resistant to removal. The extraction process is excruciatingly painful for Fuqing. The Emperor and Empress, witnessing their daughter's agony, are distraught. Fuqing endures the pain, and the Gu is finally removed. The next day, with Fuqing's sight restored, the Emperor rejoices and plans to reward Jiang Si.
