After being kidnapped and forced to work as a servant in the rear palace, former apothecary Maomao inadvertently draws the attention of the higher ranks when she investigates what's causing the emperor's infant heirs to fall mysteriously ill.

Under direct orders from the emperor himself, Maomao tries to care for an ailing Concubine Lihua, but finds her work impeded by Lihua's own ladies-in-waiting.

Gaoshun goes to Maomao to get her help in resolving the events of the garden party. Later, Xiaolan explains the purpose of the hairpins Maomao was gifted, and Maomao makes a deal with Lihaku in order to finally visit home.

Maomao confronts Fengming about the dark secret she's been hiding from her noble Lady Ah-Duo.

Gaoshun requests Maomao's help in solving an apparent poisoning case. Meanwhile, Jinshi deals with an unwelcome visitor who's taken to lingering in his office.

A discussion with Lihaku about recent events leads Maomao to realize that the mysteries she's helped to solve are connected. As the final piece of the puzzle falls into place, she rushes to stop impending disaster.

Lakan must now choose a courtesan to buy out. As a high-ranking military official, he can afford to freely choose, even from one of the Three Princesses. Who will he choose? Who does Maomao really want him to choose?