Lu Yun returns to 1983 and the Hongxing Machinery Factory. Drawing on years of experience and his superb precision-fitting skills, he takes the initiative to troubleshoot and repair imported equipment by hand, fabricating precision parts himself when the newly introduced machinery suddenly breaks down and foreign technicians seize the opportunity to make things difficult. He uncovers the true cause of the malfunction, safeguards the legitimate rights and interests of the factory and his fellow workers, and strengthens his resolve to master his craft and help the factory thrive.