As Napoleon's army advances towards Moscow, Pierre, Count Rostov and Petya attend a meeting at which Governor-General Rostopchin reads a proclamation from the Tsar. It states that the Russian army is ready to sacrifice all in defense of the country, but that he needs the financial support of rich merchants and the nobility. Pierre promises to equip a thousand men, while Petya is desperate to join up. The Tsar himself arrives and thanks those gathered for their support. Andrei sends a letter to Bald Hills warning that the advancing French army is close to the estate. The old Prince dismisses his son's advice, but Maria and Mademoiselle Bourienne begin to make plans to depart. Soon after, the Prince has a seizure while arguing with Maria and they all leave for Bogucharovo. Once there, Maria finds herself in danger when the peasants on the estate refuse to let her leave....

Julia Karagina, who is now married to Boris Drubetskoy, pays a visit to the Rostovs and they discuss the prospect of leaving Moscow. Petya has joined a Cossack regiment but in line with the wishes of the Countess, Pierre transfers him to his own regiment which is training near Moscow. Pierre is unable to decide whether he should leave for Petersburg or stay in Moscow. Andrei meets Marshal Kutuzov again and tells him that his father is dead. Kutuzov believes that the forthcoming battle at Borodino will be pointless, as all that will change is that each side will lose some twenty thousand men. He also believes that the loss of Moscow is not important. Pierre meets up with Andrei at an encampment, but the battle begins before he has left the area....