The action takes place during the Great Patriotic War. Peasant Matryona Bystrova loses her husband at the front, then her eldest son goes missing. Matryona decides to save the youngest son at all costs and shelters him from being drafted into the army in the attic of the house until the end of the war. But it turns out that saving her son, she condemns him to spiritual death, and herself to torment of conscience. A private story about the mother of a deserter grows to epic proportions...