In the library at Joseph Surface’s house, Joseph is waiting for Lady Teazle, who is late. Joseph reflects to himself that Sir Peter does not suspect him of having an affair with his wife, but he hopes he will not lose Maria as a result of this affair with Lady Teazle. The servant tells him that Lady Teazle has arrived and then goes to let her in. Joseph reflects that he cannot let Lady Teazle know that he hopes to marry Maria until he feels like she is more in love with him and under his control.
Joseph is so used to concealing his true self that it does not occur to him to end his affair with Lady Teazle and confess his hopes to marry Maria. Instead he speculates that he may be better able to manipulate Lady Teazle once they have been sexually intimate, which reflects his cynical attitude towards relationships and romance in general.
Lady Teazle enters and sees Joseph looking serious. She complains that Sir Peter is ill natured and jealous of Charles. She says she wishes that Sir Peter would allow Maria and Charles to marry, because he would stop suspecting Lady Teazle and Charles of having an affair then. To himself, Joseph says he hopes this doesn’t happen, but agrees with Lady Teazle aloud, adding that Lady Teazle would stop suspecting Joseph of having any interest in Maria if Maria and Charles were married. Lady Teazle says she believes him.
Joseph continues to lie to Lady Teazle and conceal his intention to marry Maria. Lady Teazle, who does not realize Joseph’s true character, likely believes his excuses about the scene she witnessed between him and Maria, because she thinks it would be disloyal for Joseph to try to marry a woman who loves his brother and whom his brother loves.
Lady Teazle begins to complain that her friend Lady Sneerwell spreads rumors about her, which makes Sir Peter even more suspicious. The worst part, she says, is that she is perfectly innocent and deserves none of it. Joseph says that the only solution to the problem—that is, of Sir Peter suspecting Lady Teazle of betraying him for no reason—is for her to betray him in reality. He goes on to say that it is because she knows herself to be innocent that she is careless about making sure nothing she does could cause suspicion—she is “dying from too much health.” Lady Teazle says that this is a very odd doctrine, but Joseph counters that she only finds his logic questionable because she is still not used to London high-society. She says she would be more likely to be convinced to start an affair by Sir Peter’s ill-natured treatment of her than by Joseph’s logic.
Lady Teazle has enjoyed participating in the rumor mill so long as it allowed her to exercise her wit and intelligence, but now she begins to resent its cruelty and effect on her marriage. Joseph frames arguments in lofty terms that give them an air of morality. But now, as he advocates for Lady Teazle to commit adultery, the difference between the content of his speech and the language he uses strikes her. It is by advocating that Lady Teazle sleep with him—thereby doing something she will need to lie about and conceal—that Joseph begins to expose his own true character to her.
Just as Joseph reaches to take Lady Teazle’s hand, the servant walks in to tell him that Sir Peter has arrived. Both Joseph and Lady Teazle panic: they can hear Sir Peter climbing the stairs to the room. Lady Teazle hides behind a screen. Joseph pretends to be dozing over a book as Sir Peter enters. Sir Peter approves of Joseph always trying to educate and improve himself. Sir Peter says he wants to talk to Joseph about a sensitive subject: he is very unhappy with Lady Teazle, who does not love him, and whom he suspects is having an affair. Joseph pretends to be shocked.
As this famous scene of multiple concealments begins, Lady Teazle hides behind the screen to avoid being exposed in an act of impropriety in front of her husband. But she will now be able to eavesdrop on the conversation, which will mean that both Sir Peter and Joseph’s true selves will be exposed to her. She sees how Joseph assumes an air of morality in front of the man whose wife he is trying to steal, and hears her husband’s sincere sorrow at their marital troubles.
Sir Peter tells Joseph he believes that Charles and Lady Teazle are lovers. Joseph expresses disbelief, and Sir Peter replies that Joseph’s morality may make it hard for him imagine other people’s bad behavior. Joseph agrees, but says he thinks Lady Teazle would be unlikely to be unfaithful. Sir Peter says she could have been attracted to the handsome, lively Charles and that the difference in their ages may make it impossible for Lady Teazle to love him. He says that everyone will laugh at him for marrying a much younger woman, if it comes out that Lady Teazle is having an affair. Joseph says he disown his brother if he sees proof of an affair with Lady Teazle. Sir Peter praises Joseph’s sentiments.
Sir Peter lives in terror of being the butt of people’s jokes. He takes rumors seriously, although he should know how many of them are baseless. From the jokes Lady Teazle makes and the rumors he knows are circulating, he has concluded that it is true that Lady Teazle does not love him because of the difference in their ages. Joseph, meanwhile, shows no discomfort as he hypocritically expresses shock and disbelief at the idea that Lady Teazle and Charles are having an affair.
Sir Peter says to Joseph that he wishes to make sure that he gives Lady Teazle no cause to be upset with him. He shows Joseph two drafts of the financial arrangements he is making for Lady Teazle. He has determined to give her eight hundred pounds a year and most of his money upon his death. Joseph tells Sir Peter that this is very generous, but says to himself that he hopes this will not decrease his own influence over Lady Teazle.
Sir Peter has come to realize that Lady Teazle is right about her claim on his money. He may have lived more prudently as a bachelor, but a rich man’s wife is expected to be able to live in luxury. Joseph thinks that hearing this will likely change Lady Teazle’s feelings about her husband, thus diminishing his own potential to seduce her.
Sir Peter begins to talk about Joseph’s hope to marry Maria. Joseph tries to stop Sir Peter, saying that he does not want to selfishly talk about himself when Sir Peter’s happiness in his marriage is at stake. Sir Peter continues, though, saying that he wishes Joseph would allow him to tell Lady Teazle about Joseph’s hope to marry Maria, because he thinks she would help them to arrange it.
To keep his own secret, Joseph pretends to care only about Sir Peter, but he cannot keep Lady Teazle from overhearing the truth that Joseph is pursuing Maria and her simultaneously. She also hears how he uses his lofty sentimental speeches to try to keep Sir Peter from revealing this secret in her hearing.
A servant enters and announces that Charles has come to see Joseph. Joseph orders the servant to tell Charles he is out, but Sir Peter says he wants Charles to come up. He says he will hide in the room and listen to the brothers’ conversation while Joseph asks Charles about Lady Teazle. Reluctantly, Joseph agrees. Sir Peter is about to step behind the screen when he spots the bottom of a woman’s dress. Joseph explains that a young French hat-maker was in his room on a romantic tryst, and that she hid behind the screen when Sir Peter arrived unexpectedly. Sir Peter teases Joseph for secretly being a ladies’ man, and then hides in a closet. Lady Teazle peeks her head out and asks if there is any way she can escape, but Joseph urges her back. Then Sir Peter peeks his head out, telling Joseph to be sure to get an answer from Charles. Lady Teazle pokes her head out again, and then Sir Peter again.
Sir Peter plans to conceal himself from view so that he can listen as the truth about his wife and Charles is exposed. While trying to find a hiding place, he learns that someone else is hiding in the room. Despite this revelation, Sir Peter does not wonder what else Joseph may be hiding, and takes him at his word that the skirt belongs to a seamstress. As the two spouses take turns poking their heads out of their hiding places, the precariousness of the situation is emphasized in a comic way. The truth about both Surface brothers’ reputations is going to be exposed, and the truth about the Teazles’ marriage seems unlikely to stay hidden for long.
Charles enters. He says he had heard Sir Peter was with Joseph, and asks where he has gone. Joseph says Sir Peter avoided him because he believes that Lady Teazle and Charles are having an affair. Charles laughs at this idea, saying it sounds like Sir Peter has discovered what it is like to have a young wife. Joseph tells Charles to be serious, and Charles says that he never considered pursuing Lady Teazle. At one time, he says, it seemed to him that she might be interested in him, but he is attached to Maria. Charles says that he would never deliberately do something dishonorable, but if a pretty woman with a husband old enough to be her father were to throw herself at him, he would need “to borrow a little of your morality.”
Joseph begins by taking a tone of moral superiority with his brother, chiding Charles for acting in such a way that honorable people like Sir Peter avoid him. Charles responds lightheartedly, exactly like someone with nothing to hide. Charles suggests that he sees through his brother’s feigned morality, when he raises the question of what he might do if Lady Teazle were to try to seduce him. To “borrow” Joseph’s morality might mean to reject a woman seeking to commit adultery with him, or it could mean to sleep with the woman and conceal it, taking a page out of Joseph’s book.
Charles says he is surprised that Joseph would think that he and Lady Teazle are having an affair, because Charles believed that Lady Teazle prefers Joseph. Joseph tries to hush Charles, but Charles mentions that he has seen Joseph and Lady Teazle exchange significant glances and even found them alone together. In a panic, Joseph whispers to Charles that Sir Peter has overheard everything they have been saying. Over Joseph’s objections, Charles then pulls Sir Peter from the closet. Sir Peter shakes Charles’s hand, saying he no longer suspects him, and tells Charles not to be mad at Joseph for participating in Sir Peter’s scheme to spy on him. Sir Peter believes that Charles’s suggestions that Joseph and Lady Teazle have feelings for one another were just a joke.
Even without Sir Peter discovering Lady Teazle, there is a danger that Joseph’s own behavior around Lady Teazle while in the presence of other will get back to Sir Peter. Charles does not pay attention to rumors, but trusts his own impressions, showing that, like Rowley, he is a good judge of character who understands Joseph to be a hypocrite. Charles dislikes it when things are disguised: just as he spoke plainly to “Mr. Premium,” he now insists on talking directly to Sir Peter.
The servant enters and tells Joseph that someone has come to see him. Joseph tries to persuade Charles and Sir Peter to come downstairs with him, but Charles says he wants to spend some time alone with Sir Peter. Joseph says he will go send this visitor away, and whispers to Sir Peter not to mention the hidden French girl to Charles. Sir Peter promises. Left alone, Sir Peter tells Charles that he should emulate his brother. Charles says that Joseph is too prudish to be emulated. Sir Peter cannot resist the prank, and, greatly amused, tells Charles that Joseph has a lover hidden in the room behind the screen. Just as Joseph reenters the room, Charles pulls down the screen, revealing Lady Teazle.
Charles dislikes concealment, and just as he pulled Sir Peter out of the closet, he now insists on seeing who is hidden behind the screen. Because he is open and honest about his own flaws, the consequences of this exposure do not occur to him. Sir Peter, on the other hand, is used to concealing his true feelings and motives – especially from his wife – and would have respected Joseph’s demand that he leave the woman behind the screen undisturbed.
Charles and Sir Peter exclaim in surprise. Charles asks Joseph, Sir Peter, and Lady Teazle what is going on, but no one answers him. Charles then leaves, first chiding Joseph for giving Sir Peter cause for worry, and repeating Sir Peter’s words that “there’s nothing in the world so noble as a man of sentiment!” back to him.
Charles did not mean to expose his brother’s immorality, but now that he has, he cannot help but gloat that the brother whose moral example he has been told to follow has been hypocritically hiding his true behavior all along.
After an awkward silence, Joseph stammers that he can explain everything. Sir Peter tells him to do so. Joseph gives a convoluted explanation, suggesting that Lady Teazle came to his house so that he could explain to her that he wanted to marry Maria without making Sir Peter jealous. Sir Peter sarcastically calls this a clear explanation, and then asks Lady Teazle if she will vouch for it. Lady Teazle denounces Joseph as a hypocrite, saying there is not a word of truth in what he said. She tells Sir Peter that she came to listen to Joseph try to seduce her, although she had not yet decided whether or not to be seduced.
The fact that Lady Teazle is alone with Joseph in his home without her husband’s knowledge would have been seen as proof of an affair between the two. Joseph has been caught red-handed, but still refuses to confess. He never admits to wrongdoing no matter how obvious it is that he has committed it. Lady Teazle’s explanation is honest, but it remains to be seen whether her husband will believe her and forgive her.
Joseph objects, but Lady Teazle goes on. She says that, although she cannot expect Sir Peter to trust her now, she was very touched by the tender way he talked about her to Joseph, and, even if she had not been discovered, she would have treated him differently from now on. She concludes by saying that Joseph is despicable for having tried to seduce his too-trusting friend’s wife while also trying to marry his ward (Maria), and then leaves the room. Joseph tries to object again by giving a speech about morality, but Sir Peter ignores him.
Lady Teazle tells her husband that though was she exposed in the act of considering committing adultery, his true feelings for her were also revealed when she heard him talk about the pain their arguments cause him and his intention to give her financial independence. Her manner has changed completely: she no longer teases him and sees that he deserves more respect.