This film tells the story of Zhang Si De, a model of the Chinese People's Liberation Army. In the late period of the War of Resistance Against Japan, Yan'an was in a mass production movement. The service soldier Zhang Si De (Wu Jun) is honest, unspoken, never invites merits for doing good things, works hard and never complains, and devotes himself to the Chinese revolutionary cause.

In response to the death of her husband and young son, peasant Zhang Meili founds a school in the dry desert landscape of northwest China. When cultured and chipper Xia Yu arrives from Beijing to help her out, the two women bond and learn from each other's character how to best serve the children. Various subplots include the arrival of Xia's husband, who tries in vain to persuade her to return to the city, Xia's quick abortion, and the comically clandestine relationship between Zhang and a local projectionist.