Zheng Daxiu is a veteran mechanic who has worked in an auto repair shop for twenty years. Insisting on factory-original standards and safety procedures, he comes into conflict with managers who care only about regulations and costs, resulting in his bonuses being deducted and his salary lowered. Thereafter, he strictly follows his job responsibilities, leading to workshop problems gradually being exposed and customer orders being affected. During a critical inspection, Zheng Daxiu once again demonstrates his professional competence, cooperating with retaining evidence to investigate issues such as switched-out spare parts, and the responsible parties are dealt with. Ultimately, he chooses to leave his original store, join the group's standards center, and continue passing down technical standards and the craftsmanship spirit.