Two 13-year-old Hungarian twins sent to live with their abusive grandmother during the waning days of World War II document their attempts to desensitize themselves to the physical and psychological horrors of war. As air raids lay waste to cities and starvation runs rampant, the two young brothers are driven to their grandmother's house in the country, and given a notebook to write about their experiences. Convinced that their future is one of intense suffering and torment, they determine that their only hope for survival is to steel themselves to the atrocities they now endure on a daily basis. Before long their emotions are muted along with their appetites, and any memories of their pampered past are completely eradicated. All the while, they strive to keep their record of the war, Le Grand Cahier, completely objective and devoid of emotion. Later, their cynicism bolstered by sights of hypocritical clergymen, cruel soldiers, and treacherous neighbors, the brothers find that life after liberation is even worse than life at war. Only once they are reunited with their parents will their vow to always remain together be put to the ultimate test.