Mabel Chiltern then enters the room, chastising her sister-in-law for complimenting Lord Goring's uncharacteristic seriousness. Mabel and Goring then engage in flirtatious banter. Goring requests a list of last night's guests and, having reconfirmed a riding date tomorrow with Mabel, leaves the scene. Mabel then recounts the travails of her courtship by Sir Robert's secretary, Tommy Trafford, to her sister-in-law, mocking his endless proposals and the ideals of husbandry.
Suddenly, Lady Markby and Mrs. Cheveley appear. After some banter, Mabel excuses herself to go play tableaux at Lady Basildon's. The unexpected visitors then explain that they have come for a diamond brooch of Mrs. Cheveley, which she lost the evening before. Of course, no one has reported it being found. After a conversation on the education of women, married life, and a number of marriage scandals, Lady Markby briefly leaves Mrs. Cheveley in Lady Chiltern's charge to pay a visit to her friend, Lady Brancaster. Though Cheveley rather pointedly attempts to extricate herself from the situation, Lady Chiltern insists that she stay.
Once alone, Lady Chiltern ends the banter abruptly, and the two confront each other. Upon discovering that it was the Lady Chiltern who made Sir Robert refuse her proposal, Mrs. Cheveley ominously demands that she have him reverse his decision; once again she asserts that she and Sir Robert make a good pair as they share a secret sin. As Lady Chiltern orders her to leave, Sir Robert enters from behind. Pointing at him with her outstretched finger, Mrs. Cheveley reveals his secret to a horrified Lady Chiltern; Sir Robert rings for Mason and has her shown out.
Though Sir Robert immediately attempts to console her, Lady Chiltern fiercely rejects him, bemoaning the unmasking of her ideal husband and death of her worshipful love. Sir Robert dramatically responds by accusing her of turning him into a false idol, making it impossible for him to confess his dark past, and thus ruining his life. He then contrasts male and female love. Whereas women demand lovers who serve as impossible objects of worship, men allow for their lovers' imperfections. For Sir Robert, true love should always forgive. Accusing Lady Chiltern of ruining him with her demands for perfection, he rushes from the room and shuts the door. Lady Chiltern pauses in horror, her fingers outstretched, and flings herself down beside a sofa, sobbing like a child.
As we are tracing the theme of marriage in this play, we can once again structure our analysis of this act according to the various commentaries on marriage delivered by its different characters. We will begin with the Chilterns.
As in Act I, the playful conversational banter in the second half of Act II ultimately gives way to a confrontation between Sir Robert and Lady Chiltern upon the revelation of latter's secret by Mrs. Cheveley. Once again, their melodramatic dialogue serves as vehicle for a discussion of love that reaffirms the conventional social values of the Victorian stage. This encounter also describes love in gendered terms, and the gender politics of this discussion are unfortunate to say the least.