The eponymous lady with the pet dog, Anna Sergeyevna, is trapped in an unfulfilling marriage with a much older man. At that time, the prevailing standards held that women should stay with their husbands come what may; they had few rights, and if they were subjected to any kind of abuse, be it emotional or physical, they were expected to accept it without complaint.
An unhappy marriage has made Anna emotionally vulnerable, which makes her especially prone to the amorous overtures of Gurov, a notorious philanderer. Gurov is an expert seducer who has engaged in numerous extra-marital affairs. In his adulterous liaisons he embodies society's general contempt for women.
When he first casts eyes on Anna Sergeyevna he sees her as just the latest notch on his bedpost, a sexual plaything and nothing more. After committing adultery with her, Gurov is initially ready to cast her aside as he has done with so many other women in the past. Yet try as he might he simply cannot get her out of his mind, and he eventually comes to realize that he's in love with her.
But even so, the road ahead for the two love-birds is strewn with obstacles. Society will not look kindly on their relationship, even if they are genuinely in love with each other. And one can be certain that, due to society's double-standards, it will be Anna Sergeyevna whose reputation will suffer.