Plot Summary

Act One
The play opens in Lady Margaret Windermere’s home, where she is arranging roses for a party later that evening in celebration of her birthday. Lord Darlington visits, and Margaret chides him for flirting with her. He contends that a woman whose husband of two years is unfaithful has a right to “console herself.”
Lady Windermere fails to recognize his oblique reference to her husband, and calls herself a Puritan with “hard and fast rules” for fidelity. Lord Darlington continues to flirt with her, but she ignores him.
He leaves and the Duchess of Berwick and her daughter, Lady Agatha Carlisle, enter. The Duchess cattily reports that Lord Windermere has been spending time and money on a Mrs. Erlynne, whose social status is questionable. The Duchess admits that her own husband has had his “little aberrations,” and assumes all men are immoral.
Yet the Duchess is anxious to marry off her daughter Agatha, saying “a mother who doesn’t part with a daughter every season has no real affection.”
After they depart, Lady Windermere looks through her husband’s desk and discovers payments to Mrs. Erlynne in his secret bankbook. When he comes in and finds her looking at it, he gets angry. He demands that his wife invite Mrs. Erlynne to their party in order to help the woman back into society. Lady Windermere flatly refuses.
He addresses an invitation to Mrs. Erlynne himself. Outraged, Lady Windermere threatens to hit the infamous woman with her new birthday fan when she arrives. Lord Windermere protests and she storms offstage.
As the curtain drops, he agonizes over what to do about the situation. Apparently there is something to his relationship with Mrs. Erlynne, for he groans “I dare not tell her who this woman really is. The shame would kill her.”
Act Two
The Windermere’s party is in full swing, and the guests are being announced. The Duchess of Berwick has advised Agatha to dance with Mr. Hopper of Australia, a prospective suitor.
Lord Augustus Lorton, brother of the Duchess, asks Lord Windermere how Mrs. Erlynne can gain respectability. It seems that Lorton hopes to marry her. He is reassured by her invitation to tonight’s ball, for it paves her way into “this demmed thing called society.”
Mrs. Erlynne appears and smoothly makes her way from guest to guest, especially the men. Their wives glare indignantly. In the meantime, Lady Windermere remains cold to her husband, and seeks comfort from Lord Darlington, who takes advantage of her mood by confessing his love and offering to take her away.
At first shocked, Margaret asks for time to see if her husband would return to her. Defeated, Lord Darlington announces that he will leave England the next day and bids her goodbye.
As the music stops and guests come back into the room, the Duchess of Berwick talks approvingly of Mrs. Erlynne to Margaret, yet advises her to get her husband away from the woman.
Agatha whispers to her mother that Mr. Hopper has proposed. With her goal in hand, the Duchess now takes full charge, insisting that the couple remain in London rather than return to Hopper’s home in Sydney.
Two gentlemen offer alternate views to Mrs. Erlynne’s presence at the ball: one says that Lady Windermere must have “common sense,” while the other credits Lord Windermere with cleverly hiding his indiscretion in the open.
Mrs. Erlynne informs Lord Windermere that Lord Lorton has proposed; in addition, he has asked for 2000 to 2500 pounds a year from him. Annoyed but compliant, Windermere exits with her to the terrace to discuss the details.
As the music strikes up again, Lady Windermere decides to run away with Lord Darlington and leave her husband. She leaves a farewell letter on her desk. Mrs. Erlynne enters and reads it.
She lies to Windermere about the letter’s contents and calls for her carriage. Lord Augustus enters with a bouquet for Mrs. Erlynne and proposes. Without responding, she instructs him to take Windermere to his club until morning, and he complies.
Act Three
Alone in Lord Darlington’s rooms, Lady Windermere vacillates between staying and going back to her husband. When Mrs. Erlynne arrives, Margaret recoils in contempt of her rival. Mrs. Erlynne pleads with her to return to her husband, denying any relationship with him.
Lady Windermere is moved when Mrs. Erlynne reminds her of her duty to her child. She tearfully decides to go home, but upon hearing voices, they both hide behind the curtains. Lord Augustus (“Tuppy” to his friends), Lord Darlington, Dumby, Cecil Graham, and Lord Windermere arrive, having been turned out of the club.
The men speak cynically of women and society as they settle into a game of cards. This scene displays Wilde’s wit as the men banter back and forth. Then Cecil sees Lady Windermere’s fan on a table. He shows it to Tuppy for a chuckle at Darlington, who has been moralizing, for apparently he has a woman in his rooms.
Windermere’s reaction to seeing his wife’s fan, however, is dramatic. He threatens to search Darlington’s rooms. Darlington refuses. Only the sudden appearance of Mrs. Erlynne, stepping out from behind the curtain, stops a probable fight. She pretends to having taken Lady Windermere’s fan by mistake. The men respond variously with contempt, astonishment, and mockery, as the curtain falls.
Act Four
Back at home, Lady Windermere lies on a sofa, wondering why Mrs. Erlynne disgraced herself to save her reputation. Lord Windermere comes in and sympathetically suggests a visit to the country. He also expresses a change of heart about Mrs. Erlynne, whom he now considers “as bad as a woman can be.”
His wife defends her and insists on seeing her once more before they depart. Lady Windermere almost confesses the truth, but Parker interrupts them. He is carrying Lady Windermere’s lost fan and Mrs. Erlynne’s card on a tray. Margaret tells Parker to invite her up, in spite of her husband’s protest.
Mrs. Erlynne enters, and apologizes for taking the fan. She announces that she is leaving England and wants a photograph of Margaret with her child. While Lady Windermere goes upstairs to find one, Lord Windermere confronts Mrs. Erlynne for causing his first quarrel with his wife, and for misrepresenting herself. It is revealed to the audience that Mrs. Erlynne is Margaret’s long-lost mother.
It is true that Mrs. Erlynne had been extorting money from him, but she has had a change of heart, too. She fails to convince him of her new sincerity, but revels in her new relationship with her daughter — who never learns that Mrs. Erlynne is her mother.
Before leaving, Mrs. Erlynne offers Lady Windermere a piece of advice: not to tell Arthur of nearly leaving him. Lord Augustus arrives and accepts Mrs. Erlynne’s explanation that she was only looking for him at Darlington’s home. He proposes to her again. Margaret comments that he is, indeed, “marrying a very good woman.”

From the Book "Plays of Oscar Wilde"