Because the Yunheng Formation of Yunxiu Mountain has been out of balance due to years of uneven distribution, coinciding with a temporary water diversion from the Medicine Valley and an early star tide, nine water veins have fallen into a backflow crisis. Pei Zhaochuan and Wen Qinglan, together with companions, investigate from the mountain gate anomalies to the old pressure relief outlet of the Medicine Valley, the Thousand-Lamp Grottoes, and the Folded Moon Terrace, uncovering layer by layer the deep-seated flaws of the old formation. Facing danger, everyone calmly seeks proof and cooperates with each other, reorganizing the main array with green-glazed lamp wicks and a spring-back diversion solution, ultimately restoring balance to the nine veins.