This Book begins with Pierre in Moscow, discontented with his life. He fears he has become what he despised seven years ago: a Moscow gentleman-in-waiting. He is also depressed at what he sees as universal hypocrisy and abandons himself to distractions instead of insoluble problems.
In Chapter II, Princess Maria and her father are also in Moscow and she has given up hopes of marrying. She has been teaching her six-year-old nephew, Nikolai, and has begun to be impatient with him. She is, however, being paid court to by Boris, but Pierre points out to her that Boris is also visiting Julie Karagin. Not long after, Boris and Julie become engaged. Around this time, in Chapter VII, Natasha visits Princess Maria, who is, after all, her future sister-in-law. Unfortunately, the two women do not appeal to each other.
Natasha is then taken to the opera and Chapter IX is a pivotal moment in the narrative. Here, Anatole notices and flirts with her with the complicity of his sister, Hlne, who is sitting in the box adjacent to Natasha. Initially, Natasha cannot understand why others are so absorbed in the opera. She only notices the artificiality. However, after sitting with Hlne she becomes intoxicated by the performance. Hlne introduces Natasha to Anatole and she is consequently intoxicated by him.
At home, Natasha believes she has lost the former purity of her love for Prince Andrei because she has also fallen in love with Anatole. Although Natasha does not know, the reader is informed that Anatole is still married to a Polish girl and that he does not think of the consequences of his actions.
It amuses Hlne to throw her brother and Natasha together and in Chapter XIII she tells Natasha he is in love with her. Natasha believes this and is convinced by the letter Anatole sends her (which has been composed by Dolohov). Natasha tells Sonya that Anatole is her master; she is his slave. Anatole forms a plan to elope with her, but this is undone by Maria Dmitrievna. She then informs Pierre, who in turn confronts Anatole and Anatole leaves for Petersburg the next day. After being informed that Anatole is already married (and that she has been deceived), Natasha attempts to poison herself. The ending of this Book is significant because it becomes increasingly evident that Pierre is in love with Natasha. He looks up to the sky and sees the 1812 comet and for him it is not an omen of horror.
With regards to the plot development from Books Four to Eight, Book Four begins with a younger Natasha declaring she does not want to marry anyone and Book Eight ends in her presumed disgrace. Her visit to the opera in this section is of enormous significance for the whole of this novel. On a literal level, it is here that she encounters, and is flattered by, the attentions of Anatole. The consequence of this meeting is that he destroys the relationship she has had with Prince Andrei and her good name is made questionable.
This night at the opera is also figuratively relevant as at first Natasha is unconvinced by the superficial nature of the stage production. She gradually becomes intoxicated by the artifice, however, just as she becomes influenced by the attentions of both Hlne and Anatole.
Pierres developing love for Natasha is also spelled out at the end of this Book as he attempts to bring comfort to her after she has tried to poison herself. His perspective of the comet as an omen of good fortune is an indicator of happier future events. The use of the sky as a trope for optimism in human relationships and as representative of the love of God is also used again here, as it was when Prince Andrei looked to the heavens after being injured in battle.