Where is the ball scheduled to take place in A Doll's House?

Nora and Torvald have been invited to attend a fancy-dress ball at the home of their neighbors, the Stenborgs. Nora will wear the costume of a gypsy-girl and dance the tarantella, which she's been practicing intensively. Yet Nora's not really entering into the party spirit. All kinds of dirty secrets have been revealed, putting a dampener on her mood. As well as Krogstad's sordid little blackmail scheme, there's the little matter of Dr. Rank's shocking admission that he's in love with Nora. All in all, this isn't ideal preparation for what's supposed to be a fun night up at the Stenborgs' place.
To make matters worse, Nora gets into a blazing row with Torvald. Nora, fearful of Krogstad's attempts to blackmail her, has interceded with her husband to get Krogstad his job back, but all to no avail. Torvald just won't budge, and after their ensuing argument, Nora storms off, angered by Torvald's stubbornness and insensitivity.
Nevertheless, the Helmers still attend the costume ball, at which Nora dazzles everyone with the intensity and sensuality of her dancing. This isn't surprising when you consider how hard she practiced. Though, this was a way of distracting Torvald so that he wouldn't open his mail and read Krogstad's lurid revelations about Nora's financial wrongdoings.