In the first half of the 20th century, Chinese society was at a crossroads of historical development, with a complicated political situation and a surging workers' movement. In the ancient town of Changxindian in the southwest of Beijing, Kang Benshan, a young and poor locomotive factory worker, dreamed of "becoming a great craftsman, repairing the most difficult machines, and building the best trains". Under the guidance of the party organization, he and progressive elements such as Wang Ranqiu, Wang Sen, and Wu Shiju united the workers to establish a workers' club, escort strike donations, protect technical backbones, resist Japanese aggression, and arrest Kuomintang spies, and gradually grew and matured in the process of fighting against various reactionary forces. After the founding of the People's Republic of China, he and Wang Ranqiu, as an engineer couple at the Erqi Locomotive Factory, made important contributions to the development of new locomotives and became true "great craftsmen".