In 19th century Russia, Anna Karenina (Greta Garbo), the wife of chilly stateman Alexei Alexandrovitch Karenin (Basil Rathbone), is introduced to handsome, dashing Count Vronsky (Fredric March), an officer in the Imperial Guards. Vronsky is immediately attracted to Anna, who hopes to remain faithful to her husband, mostly because of her beloved son Sergei (Freddie Bartholomew). However, Vronsky persists, and Anna eventually falls in love with him. Eventually, Karenin learns of his wife's affair, and accuses her of destroying their family, while elsewhere, Vronsky's superior orders him to end the relationship with Anna. At first, Anna finds it impossible to accede to Vronsky's demands that she choose between him and Karenin, but when Vronsky is injured in a horse race with Karenin and her husband refuses to let her help her lover, her decision is made: she loves Vronsky. Karenin banishes her from her home, and refuses to allow her to see Sergei. She and Vronsky go to Venice where, for a time, they are happy. Back in Moscow, Anna defies Karenin and visits with Sergei, then learns that Vronsky is about to join his regiment in the Serbo-Turkish war.