After bumping into Vronsky, Karenin goes off to the opera and stays for two acts.
When he gets home, he checks to make sure Vronsky's coat is not in the coat stand.
Instead of sleeping, Karenin paces back and forth thinking about his wife. He's angry that she failed to comply with his one request: that Vronsky not come to his house. Karenin feels that he should follow through on his threat of divorcing Anna and taking their son away from her.
In the morning, Karenin is even angrier. He goes into Anna's room (where she is sitting), grabs her keys, and starts ransacking her desk in front of her.
He forcibly takes Vronsky's letters from her.
Karenin says many terrible things to Anna and she feels the full truth of his statements.
In their conversation, Karenin criticizes her harshly for being an unfaithful woman. When Anna protests that he has no right to insult her, Karenin claims that he's only speaking factually.
Karenin tells Anna that he is leaving for Moscow tomorrow and not returning to the house. Anna will be hearing from his lawyer.
Then Karenin tells Anna that Seryozha will go to his sister.
Anna is distraught. She points out that Karenin doesn't even love the boy, but only wants to hurt her by taking him away. She begs that he leave Seryozha with her at least until she gives birth.
Karenin flushes red and leaves the room without a word.