Gurov has been in Yalta for two weeks when he hears about a new arrival, the lady with the dog. He spots her one day wearing a white beret and walking her Pomeranian.
The narrative reveals some background info on Gurov: he's under forty, has three kids, dislikes his wife, dislikes women in general, carries on a number of affairs with neither regret nor much emotion. Women like him, and he likes women.
He bumps into the lady with the dog several times. One day, when she sits at the table next to him for lunch, he strikes up a conversation with her. He learns a bit about her background and reveals some of his own: he studied the arts, yet has a job at a bank now in Moscow.
That night, alone in bed, Gurov thinks about Anna, decides there's something pathetic about her, and falls asleep.
A week later, while they're out together, Gurov kisses Anna. He invites himself back to her hotel room and she complies.
Gurov ruminates on the different reactions different women have to sex, and compares Anna to the others. After they sleep together, when she laments her new status as a fallen woman, Gurov quickly grows bored. He takes her to Oreanda, where they hang out until dawn.
The affair continues until Anna is called back home to S. by her husband. Gurov returns to Moscow shortly after her departure.
At home, he throws himself into city life and expects to forget Anna quickly. He doesn't. He longs to tell someone about his time with her, but he doesn't know anyone and doesn't understand it well enough to do so anyway.
Finally he gives up and travels to S. He finds Anna's house and sees an old woman walking the dog. Afraid to approach, he returns to his hotel room to take a nap.
The next night he goes to see the opening performance of The Geisha, hoping that Anna will be there. She is. While her husband is out smoking, he approaches and greets her.
When Anna begs him to leave, Gurov does, believing her promise to come visit him in Moscow.
Anna does start visiting, and Gurov meets her in a hotel room whenever she is in town.
One morning, as he makes his way to the hotel and walks his daughter to school, Gurov muses that he has two lives, one secret and valuable, the other public and worthless to him.
When he arrives at the hotel room, he tries to comfort a distraught Anna. He realizes he is completely in love with her. The two of them try to devise a plan for the future. They know that the affair is not going to end any time soon, and that there is along and difficult road beginning ahead of them.