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.
As the studio darkens, Hialmar plunges deeper into the "night side of existence," discovering the extent to which he does not occupy the place he imagined in the household—that of father and provider. Instead, he has been supplanted by another patriarch, Werle. What is worse, Werle has played freely with his family and appears to attain the "true marriage" nevertheless. He finally marries his housekeeper and remains a man of respect, completely absolved of his past sins. Thus Hialmar projects a divine order that disciplines the unruly patriarch before these injustices. Werle has been stricken blind for his "hoodwinking." It is not for nothing that, from Oedipus onward, blindness is the traditional punishment for the accession to forbidden sexual knowledge. If blindness figures her as divine punishment, the blindness Hedvig apparently inherits from Werle is perhaps apiece with the revenge the woods would exact from both the clans.
The climax of Hialmar's ruin is certainly his discovery and repudiation of Hedvig as another's child. The patriarch's claim on Hedvig forces her dispossession of her beloved father. Like the enigma of the forestry scandal, the secret of Hedvig's parentage has lurked in the household throughout the play. Hedvig prays at night because she senses that she has something to be scared of. Indeed, Hedvig readily intuits the household's secret when Hialmar repudiates her: daddy's girl might not be her father's daughter. One wonders if her excessive affection for Hialmar lies in this fear. Abandoned by her father, Hedvig now explicitly positions herself as the wild duck. Like the duck, she has been torn from her family, no longer knows her place of origin, and has been adopted strangers.
Despite the ruin he has brought to the household, Gregers will continue to preach his gospel. The disjuncture between his fanatical exhortations—that the family should seek "true frame of mind for self-sacrifice and forgiveness"—and the suffering of the Ekdals is comic and grotesque.
As with all missionaries, the aggressive impulses that underpin Gregers's crusade are not immediately accessible to him even if his cruelty toward the Ekdals is all too obvious. This cruelty is especially clear in his demand that Hedvig offer her father the wild duck as sacrifice. Only by destroying something of herself will her father know her love. Once again, Ibsen makes the disjuncture between Gregers's propositions and the welfare of the household clear. As Hedvig will vaguely sense in the following act, such an act can only function as such a sacrifice within Gregers's salvationist delusions. Upon waking the next morning, Hedvig can only find Gregers's proposal useless, making her ultimate demise tragically ironic. Indeed for Hialmar to understand its significance, Gregers will have to appear on the scene as a triumphant translator, explaining why the death of a duck would assure a father of his daughter's loyalty. Gregers and the "claims of the what-you-may-call-it" have little place in this world.