Young Lin Ye's ancestral medicinal herb garden is forcibly demolished. Unscrupulous businessman Ma Tengfei recklessly promotes high-sugar purple sweet potatoes, killing natural predators and abusing chemical rodenticides, unknowingly setting off a devastating plague of mutated rats. Mocked and driven into a corner by the villagers, Lin Ye takes an unconventional approach: he leases an abandoned red-brick kiln and breeds king snakes to establish an ecological food chain. He warns everyone in advance, but nobody believes him. By the time the rat infestation erupts, the entire village is on the brink of bankruptcy. Lin Ye seizes the opportunity to exchange ecological pest control for the return of his land, produces rare medicinal snake gallbladders, and earns enough money to pay for his sick younger sister's treatment. Rejecting chemical pest-control methods, he leads the villagers in building a pollution-free, sustainable medicinal herb production base. By protecting nature and restoring ecological balance, he finds a path to lasting prosperity.