Anna Karenina, a handsome woman in her late twenties, is visiting her brother, Stiva. She is travelling alone, without husband or son, for the first time. On the train meets a dashing officer, Count Vronsky. Also on the train is Constantin Levin, a brooding intellectual.
Levin runs into Stiva at the station confesses he's come to ask Kitty's sister-in-law, to marry him. Stiva warns Levin he has a rival in Vronsky. Stiva greets Anna and we hear the reason for her visit. Stiva has had an affair and
his wife, Dolly, has found out. Anna has come to ask Dolly to forgive him, but first she chastises Stiva.
The scene changes to the home of eighteen year-old Kitty, whither Dolly has fled. Anna arrives and tells Kitty about seeing Levin. Kitty suspects the reason for his return. Levin then and proposes. Reluctantly Kitty turns him down. Just then, Stiva arrives with Vronsky. Anna comes downstairs, having smoothed things over with Dolly. She recognises Vronsky as the attentive officer from the train. Stiva goes off to speak to Dolly, leaving the other four.
A week later, Anna is returning home. At a small station between Moscow and St. Petersburg, Anna steps outside for some air and is surprised to see Count Vronsky. He brazenly tells her he has followed her. She rebukes him and returns to the train.
The next morning, she arrives home to her husband, the much older Karenin, and her eight year-old son, Seryozha. Though both are glad to see her, she can't help feeling disappointment.
Meanwhile, Levin has returned to his country estate and sworn to forget Kitty. And Kitty, unknown to Levin, has fallen ill. She realises now she has turned down a man she liked in favour of a man who loves someone else.
Back in Petersburg, Anna keeps running into Vronsky at social occasions. Though she continues to rebuke him in words, her feelings betray her. That same night, Karenin decides to confront Anna about her behaviour. Unfortunately, in his desire to seem dispassionate, he convinces her that all he cares about is appearances. After a brief mental struggle, Anna orders the carriage and sets out for Vronsky's apartments. They declare their love for each other.
Several months have passed. Anna and her husband now hardly speak. While Karenin is at work, Anna summons Vronsky to her home. She tells him that she's pregnant with his child. He insists they run off together, but Anna can't bear to leave her son. Karenin returns and the scene turns ugly. Anna asks for a divorce and she and Vronsky run off to Italy, leaving her son behind.
Stiva visits Levin at his country estate. While hunting, he tells Levin about Vronsky and Anna, and hints that Kitty might welcome another proposal. Levin insists he's over her.
In Italy, Anna has given birth to a little girl, but finds that strangely she feels no affection. She misses her son, she feels isolated, and she senses Vronsky's growing boredom.
Back in Moscow, Kitty is preparing for a trip when Levin arrives unexpectedly. He proposes again, and this time she accepts. Kitty, learning that Anna has returned to Moscow, visits to tell her the good news. Anna can't help contrasting Kitty's hopeful future with her own. Karenin has agreed to a divorce but won't give up Seryozha. And though she and Vronsky are to be wed, Anna senses he's tired of her. While Vronsky is visiting his mother, Anna resolves to go to St. Petersburg and see her son on his tenth birthday.
In Petersburg, we see a changed Karenin. The loss of Anna and his new responsibility for his son have softened him. After he sends Seryozha to bed, Anna arrives and begs to see the boy. Karenin tells her he has told Seryozha she's dead. Anna is furious, but Karenin convinces her that Seryozha is better off without her.
Anna returns to the railway station in despair. She has lost her son and is marrying a man who no longer loves her. She decides to end her life, but first imagines seeing her son one last time. Then she walks offstage into the light of an approaching train. In the last scene, a remorseful Vronsky says goodbye to Stiva before going off to war, while at the same time, we see Levin and a pregnant Kitty happily in love on his estate.