An old flower farmer named Lao Fang, who looks like an ordinary person who has nothing to do with the world, is actually a folk expert who is proficient in herbal medicine and poisons. Lao Fang found a sachet under his daughter Ari's favorite peony flower that she had sewn before she got married. With his keen sense of smell, he sniffed out a highly poisonous herb - Gelsemium elegans - that was cleverly mixed into the unique family spice formula of the sachet. Lao Fang instantly understood that this was not an unintentional mistake, but a desperate distress signal sent by his daughter, who had been missing for two years, from her husband's family, the wealthy Qin family in Yunzhou.
