In Liuhe Village, young returnee Chen Qinglin faces ridicule from the entire village and angry scolding from his father as he sets up a shed on a hillside to raise doudan caterpillars, creatures everyone else avoids. People laugh at him for neglecting proper work, while others secretly try to sabotage him. Yet he grits his teeth, perseveres, and devotes himself to mastering breeding techniques. These tiny caterpillars conceal a lucrative business opportunity. Overcoming obstacles ranging from sales channels and diseases to malicious suppression, he leads the villagers in forming a cooperative and turns insignificant insects into a thriving industry, staging an inspiring comeback story of turning bugs into gold.