The Country Wife is more neatly constructed than most Restoration comedies, but is typical of its time and place in having three sources and three plots. The separate plots are interlinked but distinct, each projecting a sharply different mood. They may be schematised as Horner's impotence trick, the married life of Pinchwife and Margery, and the courtship of Harcourt and Alithea.
1. Horner's impotence trick provides the play's organising principle and the turning-points of the action. The trick, to pretend impotence to be allowed where no complete man may go, is (distantly) based on the classic Roman comedy Eunuchus by Terence. The upper-class town rake Harry Horner begins a campaign for seducing as many respectable ladies as possible and thus cuckolding or "putting horns on" their husbands: Horner's name serves to alert the audience to what is going on. He spreads a false rumour of his own impotence, to convince married men that he can safely be allowed to socialise with their wives. The rumour is also meant to assist his mass seduction campaign by helping him identify women who are secretly eager for extramarital sex, because those women will react to a supposedly impotent man with tell-tale horror and disgust. This diagnostic trick, which invariably works perfectly, is one of The Country Wife's many running jokes at the expense of hypocritical upper-class women who are rakes at heart.
Horner's ruse of impotence is a great success, and he has sex with many ladies of virtuous reputation, mostly the wives and daughters of citizens or "cits", i.e. upwardly mobile businessmen and entrepreneurs of the City of London, as opposed to the Town, the aristocratic quarters where Horner and his friends live. Three such ladies appear on stage, usually together: Lady Fidget, her sister-in-law Mrs Dainty Fidget, and her tag-along friend Mrs Squeamish—names that convey both a delicate sensitivity about the jewel of reputation, and a certain fidgety physical unease or tickle—and the dialogue gives an indefinite impression of many more. The play is structured as a farce, driven by Horner's secret and by a succession of near-discoveries of the truth, from which he extricates himself by aplomb and good luck. A final hair-raising threat of exposure comes in the last scene, through the well-meaning frankness of the young country wife Margery Pinchwife. Margery is indignant at the accusations of impotence directed at "poor dear Mr. Horner", which she knows from personal experience to be untrue, and is intent on saying so at the traditional end-of-the-play public gathering of the entire cast. In a final trickster masterpiece, Horner averts the danger, joining forces with his more sophisticated lovers to persuade the jealous Pinchwife to at least pretend to believe Horner impotent and his own wife still innocent. Horner never becomes a reformed character but is assumed to go on reaping the fruits of his planted misinformation, past the last act and beyond.
2. The married life of Pinchwife and Margery is based on Molière's School For Husbands (1661) and School For Wives (1662). Pinchwife is a middle-aged man who has married a naive country girl in the hope that she will not know to cuckold him. However, Horner teaches her, and Margery cuts a swath through the complexities of London upper-class marriage and seduction without even noticing them. Restoration comedies often contrast town and country for humorous effect, and this is one example of it. Both Molière in the School For Wives and Wycherley in The Country Wife get much comic business out of the meeting between, on the one hand, innocent but inquisitive young girls and, on the other hand, the sophisticated 17th-century culture of sexual relations which they encounter. The difference, which would later make Molière acceptable and Wycherley atrocious to 19th-century critics and theatre producers, is that Molière's Agnes is naturally pure and virtuous, while Margery is just the opposite: enthusiastic about the virile handsomeness of town gallants, rakes, and especially theatre actors, she keeps Pinchwife in a state of continual horror with her plain-spokenness and her interest in sex. A running joke is the way Pinchwife's pathological jealousy always leads him into supplying Margery with the very type of information he wishes her not to have.
3. The courtship of Harcourt and Alithea is a conventional love story without any direct source. By means of persistence and true love, the witty Harcourt, Horner's friend, wins the hand of Pinchwife's sister Alithea, who is, when the play opens, engaged to the shallow fop Sparkish. The delay mechanism of this story is that the upright Alithea holds fast virtuously to her engagement to Sparkish, even while his stupid and cynical character unfolds to her. It is only after Alithea has been caught in a misleadingly compromising situation with Horner, and Sparkish has doubted her virtue while Harcourt has not, that she finally admits her love for Harcourt.