Gregers applauds the ambivalent Hialmar. Hialmar admits that Hakon Werle and Mrs. Sorby's union revolts his sense of justice. It appears that they have come to realize the true marriage, one founded on complete confidence and unreserved candor, confession and absolution. It seems that providence does not exist. Hialmar does recognize the "guiding finger of fate," in Werle's imminent blindness. Such is God's retribution for his lifetime of hoodwinking.
A breathless Hedvig then appears at the door. She passed Sorby on her way out and received a birthday gift. Hialmar demands that she present it. Hedvig withdraws an envelope, hoping that the good news will repair the broken household. Hialmar reads the letter. Werle has promised a monthly income to Old Ekdal which will pass onto Hedwig upon his death. Gregers warns that Werle is trying to buy him off. He told him this morning that Hialmar was not the man Gregers imagined. Gina sends a bewildered Hedvig into the kitchen.
Hialmar methodically tears the letter in half and places it on the table. He confronts Gina anew and wonders whether Hedvig is his and whether Werle facilitated their marriage for fear of scandal. Defiantly, Gina replies that she does not know. Hialmar announces that he has no longer has a place in the house and dons his overcoat. Gregers insists that the family must be together to attain the "true frame of mind for self-sacrifice and forgiveness."
Hedvig runs out, and Hialmar rejects her and flees. A sobbing Hedvig flings herself on the sofa. Gina goes after Hialmar. Hedvig wonders why her father no longer wants her and whether it is because she is not his child. Gregers responds evasively. Hedvig moans that Hialmar should almost love her more if this is the case—just like the wild duck.
Gregers turns the conversation to the subject of the duck. Hedvig relates Hialmar's threat to kill the duck. She has prayed for the duck's safety every night; she has taken to prayer ever since Hialmar's near-fatal illness. Gregers suggests that Hedvig sacrifice the duck, her most precious possession, to prove her love for her father. Desperately Hedvig decides to ask grandfather to shoot it.
Gina returns and reports that Hialmar has gone drinking with Relling and Molvik. She sighs that Relling was right: creatures that preach "the claims of the what- you-may-call-it" only bring ruin.