Shen Qinghe, a university student, returns to his hometown to promote an eco-friendly lotus root and fish farming system. He encourages villagers to reduce pesticide use and let fish and shrimp control pests while enriching the soil. However, village chief He Youde and villagers like Zhou Dabiao strongly oppose his ideas. The entire village decides to spray pesticides, with only Aunt Zhao agreeing to follow Shen Qinghe in testing his approach. Initially, the lotus leaves in the sprayed fields flourish, but when harvest time arrives, the lotus roots are found to contain excessive pesticide residues, and buyers reject the entire crop. Meanwhile, Aunt Zhao's pesticide-free lotus roots and eco-raised fish pass inspection and receive high-priced orders from restaurant businesses. After suffering repeated setbacks, the villagers finally realize their mistake and join Shen Qinghe in establishing an ecological lotus root cooperative with unified farming standards and strict quality control.