In A Doll's House, Ibsen has taken the more traditional five act play and combined the elements in the three acts. In the first act, we learn how Nora is living almost a double life, deceiving her husband as she must keep her secret. She took a loan illegally and Torvald will never tolerate such behavior, regardless of the motives and he must never find out what his "little squirrel" has done. The audience is also made aware of the threat of the ever looming Krogstad, who knows Nora's little "secret."
Dramatic irony is a continuing feature of A Doll's House and the audience is aware of the conflicting situations that are created. Even at the beginning, when Nora eats macaroons and then blatantly lies about it, ensuring she wipes her mouth for fear of discovery by her husband who treats her like a child, chiding her and patronizing her for being a "little spendthrift....making the money fly again," the audience knows there is a discrepancy in the relationship as it is clearly not an equal partnership.
As Torvald presses Nora for the truth about the macaroons and whether she has in fact eaten any, even going so far as to suggest she looks "suspicious," she is emphatic in her denial. Speaking to her in the third person also adds to the drama created. It is ironic that Nora and her "little Christmas secrets" are far more serious and will ultimately end their relationship.
As the play progresses, the subtlety will make way for more obvious references and the seemingly cursory "suspicion" will be recognized as more than it at first appears. Whilst the audience does not yet understand the implications of Nora's deceit, the albeit indirect references, such as when Nora chats to Mrs Linden about Torvald's new job and, strangely, finds it necessary to mention that he won't get involved in "business that's the least bit — shady" allude to far more serious "secrets."
The situation is confirmed when Nora reveals that she loaned money fraudulently. Ibsen has been preparing the audience for this revelation with his understated hints about her "secret" and now the plot develops and the audiences suspicions are substantiated as we, at first think Nora inherited the money, only to discover that all is definitely not as it seems and Nora forged her father's signature.
This knowledge creates suspense as the audience already has a carefully-crafted image of Torvald, stereotypical, paternal and definitely not tolerant of any "shady" dealings. Everything now makes sense an the audience can prepare itself for what will inevitably follow.