Two important guests at Princess Betsy's party, Liza Merkolov and Sappho Stolz, both belong to a new, select social circle that is openly hostile with Anna's. To make things even more awkward, Liza Merkolov's admirer, an old man named Stremov, is one of Karenin's enemies in the office. So Anna had initially not wanted to go to this gathering, but she changes her mind because she wants to see Vronsky.
Anna arrives early and sees Vronsky's footman; she remembers only then that Vronsky had said the day before that he was not going to attend the party.
It's already too late for her to turn back or to send a note with Vronsky's footman, so she enters.
Betsy and Anna go have a cozy chat over tea.
Anna lies and says that she can't stay long, because she says she promised to go see Countess Vrede.
Betsy takes the note from Vronsky's footman and tells Anna that Vronsky can't come today. Although Anna is certain that Princess Betsy knows all, the casual way that she mentions Vronsky to Anna makes it appear as though she genuinely knows nothing of the affair.
They make small talk about the party's guests, but Anna can tell by Betsy's face that her friend is formulating a plan.
Betsy says that she has to respond to Vronsky's note, and writes something. Then she leaves Anna in the room for a moment. Anna runs over and writes her own note to Vronsky asking him to be at Vrede's garden at six o'clock.
Betsy sends off the note.
Betsy and Anna talk about Lisa Merkolov, who admires Anna. In fact, Betsy tells Anna that Liza has described Anna as "a real heroine from a novel and that if she were a man she would have committee a thousand follies for [Anna]" (3.17.22).