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.
Maomao tries to settle into her promotion to lady-in-waiting and food taster, but struggles to fend off both boredom and the overly-familiar Jinshi. That is, until she gets an assignment of her dreams: to concoct an aphrodisiac.
Tasked with investigating a ghostly woman dancing nightly on the palace walls, Maomao finds a sleepwalking Concubine Fuyou. But with no medicinal cure for sleepwalking, she's forced to dig deeper to find the real reason behind Fuyou's affliction.
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.
A eunuch stricken by a curse comes begging for aid. Meanwhile, the rear palace buzzes with excitement as everyone prepares for the upcoming garden party, and Gyokuyou's ladies-in-waiting aren't about to let Maomao get away without dressing her up.
Maomao does her best to navigate the complex social situations at the garden party, including meeting the other Upper First rank concubines. But once she settles down to do her work as a food-taster, she discovers a surprise in a bowl of soup.
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's peaceful morning at home is interrupted when she's called in to investigate an apparent double suicide at one of the local brothels.
An older acquaintance of Jinshi's dies while drinking at a party. A servant's body turns up in a moat. Both deaths are written off as self-inflicted, but Maomao's keen observations tell her that there's more to both stories.