Mr. Tachit and his son Ralph live at his Gardencourt estate forty miles from London. Mrs. Tachit travels a lot and is in her husband’s house only a month in a year. She spent the winter at home, in America, met her niece there and wrote to her husband and son that she had invited a young girl to stay with them in Gardencourt. Father and son Tachita, together with their friend Lord Warburton, are waiting for Mrs. Tachit to arrive and wondering what her niece will be like. While they are exchanging witticisms, a girl of rare beauty appears - this is Mrs. Tachit Isabella Archer's niece. Men greet her kindly, although they had never heard of her before: Mrs. Tachit was in a quarrel with her late sister's husband and only after his death went to Albany to see her relatives. A smart, sincere girl quickly gains universal sympathy.

Ralph faithfully takes care of the old father, although he himself is seriously ill: because of the weak lungs, he had to leave the service. Feeling that he will not live long, Ralph wants to spend the rest of his days with the greatest - as much as possible in this situation - pleasantness. He discovers the joy of contemplation. Isabella arouses his interest, and he talks with enthusiasm to her. The English conventions are new to Isabella, she is used to freedom, She loves to do everything in her own way, but still wants to know what should not be done here. “To do just that?” - asks Mrs. Tachit. “No, to be able to choose,” Isabella answers.

Seeing Isabella’s passion for everything romantic, Lord Warburton invites her with her aunt and Ralph to his possession of Locley, where he and his sisters welcome guests. Isabella receives a letter from her friend Henrietta Stackpole, a correspondent for the New York Interviewer. Henrietta comes to England, and the Tachites invite her to stay. The inhabitants of Gardencourt are overly energetic and somewhat intrusive Henrietta with good-natured irony. Henrietta is very fond of America and criticizes all European foundations and customs. Mrs. Tachit does not like her, but considers herself not entitled to tell Isabella with whom she should be friends.

Caspar Goodwood, a young man from Boston who was passionately in love with Isabella, arrived in England on the same boat with Henrietta. Isabella is alarmed: she is afraid that Goodwood would not come directly to Gardencourt, but he sends a letter asking for a meeting. Before Isabella left America, he made her an offer, to which she refused. Goodwood does not accept defeat and does not lose hope of winning her heart. As soon as Isabella reads Goodwood's letter, Warburton appears. He makes an offer to Isabella, but the girl believes that they still know little of each other. She promises to think and write to Warburton. Isabella tells Mr. Tachit about Warburton’s proposal, but it turns out that he already knows about him from Warburton himself. Isabella likes Warburton, but she still does not want to get married, she wants to be free. She leaves the Goodwood letter unanswered, and Warburton responds with a polite refusal.

Henrietta asks Ralph to invite Goodwood to Gardencourt - she favors her compatriot because she does not want Isabella to marry some "soulless European." But Goodwood, having received an invitation not from Isabella, but from Ralph, refers to urgent matters and does not come. Lord Warburton is trying to find out the reason for Isabella's refusal, but the girl can not really explain anything. “I can't turn my back on my path,” she says. Isabella understands that peace, honor, wealth, a chosen position in society await her with Warburton, but she consciously rejects all this. The Tachites are amazed that Isabella refused such a brilliant groom.

Isabella and Henrietta decide to go to London. Ralph is called to accompany them. In London, girls meet Ralph's friend Mr. Bentling, who readily accompanies Henrietta everywhere, admiring her education and bold judgments. While Bentling shows Henrietta the sights of London, Ralph talks with Isabella. He is very interested to know "what path the young lady will choose to reject Lord Warburton." When Isabella returns to the hotel, she is informed about the arrival of Goodwood. She understands that Henrietta arranged their meeting by telling Goodwood which hotel they were staying at. Isabella asks Goodwood not to pursue her. Upon receiving the news that Mr. Tachit is in serious condition, Ralph and Isabella return to Gardencourt. Mrs. Tachit’s girlfriend, Madame Merle, is a socialite there, provoking Isabella's admiration for her impeccable manner of holding. This woman of strong feelings, able to keep them in check seems to Isabella to be an ideal. Ralph does not like Madame Merle, although she does not say so directly. Mr. Tachit advises Ralph to marry Isabella before his death, but Ralph realizes that he is seriously ill and will not live long. He asks his father to change his will and leave Isabella half of the amount that he assigns to him. Ralph believes that in order to fully demonstrate all her abilities, Isabella needs money - then she will gain complete freedom and independence. Isabella is a proud girl and will not accept money from Ralph - so he asks his father to take on the role of her benefactor. Mr. Tachit dies, and Isabella receives seventy thousand pounds by will.

Isabella and Mrs. Tachit go to Paris, where Isabella meets Edward Rosier, whom she knew as a child - their fathers were friends. Now Rosier is a well-mannered young man collecting a collection of art objects. Mrs. Tachit decides to visit Ralph in San Remo, where he spends the winter. Isabella rides with her. The girl asks her cousin why suddenly his father left her such a big inheritance, but Ralph does not reveal the truth to her. Six months later, in Florence, Madame Merle introduces Isabella to her friend Mr. Ozmond. Madame Merle tells Ozmond that Isabella is a lucrative party, and besides, she is beautiful, smart and virtuous. Ozmond is a widower, the father of fifteen-year-old daughter Pansy, raised in a monastery and just left there. At first he refers to Madame Merle's intention to marry him skeptically, but, having met Isabella, he cannot but appreciate her merits. Ralph refers to Ozmond without any affection, considering him "expressionless." Isabella Ozmond likes her sophistication, originality and significance. The sister of Ozmond, Countess Gemini does not like Madame Merle and wants to warn Isabella from her brother, but the Countess’s reputation is such that no one listens to her opinion.

Ozmond often comes to Isabella, and Mrs. Tachit, with whom she lives, begins to worry. But Ralph reassures his mother, saying that Isabella will not accept the courtship of Ozmond. Yes, and Mrs. Tachit herself believes that it would be foolish to refuse to peer England to be satisfied with "an unknown American amateur, middle-aged widower with an absurd daughter and dubious income." Ralph invites Isabella to go to Rome. Henrietta and Bentling are also going there. Ozmond tells Isabella that she would like to be there with her, and she invites him to join their company. Madame Merle rejoices: everything goes according to her plan. In Rome, Isabella accidentally meets Warburton, who still loves her. Warburton and Ralph exchange opinions about Ozmond: they both do not like, and they hope that Isabella will not marry him. Before Isabella left Rome, Ozmond declared her love to her. Isabella leaves and travels for a year, first with her aunt, then with her sister, then with Madame Merle. Having visited Greece, Turkey and Egypt, the ladies return to Italy, where Isabella settles in Rome with Madame Merle. Ozmond arrives there for three weeks and visits them every day. When Isabella arrives at her aunt in Florence, Goodwood returns to her. Upon learning of Isabella's upcoming marriage, he hastened to come, "to hear her voice." Seeing that she was not happy with him, Goodwood promises to leave tomorrow. Aunt is not enthusiastic about Isabella’s choice, but prefers “not to interfere in other people's affairs”. Ralph arrives, he is trying to dissuade Isabella from marriage with Ozmond, but to no avail.

It takes several years. Rosier accidentally met Pansy and falls in love with her. Rosier is not rich, and Ozmond dreams of a better party for her daughter, especially since she raised her so that, although she loves Rosier, she will never dare to disobey her father. Rosier regularly visits the Ozmons, he hopes for the sympathy of Isabella, who is very attached to her stepdaughter. Warburton arrives in Rome and comes to Isabella to pay his respects. He came with Ralph, but Ralph is so sick that he cannot come. Hearing about this, Isabella promises to visit her cousin tomorrow. Warburton is trying to find out if Isabella is happy in marriage. She says she is very happy. Warburton begins to look after Pansy, and Ozmond wants to give him a daughter. Neither the big age difference, nor the fact that Pansy loves the other doesn’t scare him - Warburton is noble and rich, and that is what Ozmond needs. Warburton is about to ask for Pansy's hands. One day, Isabella accidentally catches Ozmond with Madame Merle, and something in their treatment of each other worries her - she begins to think that they are connected by some kind of close bonds, much closer than the bonds of friendship. Madame Merle takes Pansy to heart, She, like Ozmond, believes that Warburton is a great couple for Pansy. Isabella is afraid of Ozmond, but she is sorry for her stepdaughter. She tells Warburton that Pansy loves Rosier. In addition, she suspects that the forty-two-year-old Warburton is not so passionately in love with the girl, but subconsciously wants to be closer to Isabella herself.

Upon learning that Pansy does not love him, Warburton decides not to make her an offer and leaves. Ozmond is furious: he believes that Isabella upset Pansy’s marriage with Warburton. Three days after Warburton's departure, Goodwood arrives in Rome. He is unhappy, and Isabella feels guilty before him. But she herself is deeply unhappy, although pride does not allow her to admit it. Ozmond was an empty, calculating man. Isabella feels that he and Madame Merle deceived her, made a toy in her hands. She understands that Ozmond married her for money. Goodwood regularly visits Isabella on Thursdays when she hosts receptions. She introduces him to Ralph and asks Goodwood to take care of her cousin. Ralph wants to return to England, but he cannot go alone: ​​Henrietta and Goodwood are volunteered to accompany him. Isabella promises Ralph to come when he calls her. “I will save such joy in the end,” Ralph answers.

Rosier tells Isabella that he sold his collection of trinkets and earned fifty thousand dollars for it. He hopes that Ozmond will have mercy on him, but Isabella realizes that Ozmond will never agree to give him a daughter. Ozmond temporarily sends Pansy to the monastery, so that she would be alone, think, rest from society.

After receiving the news that Ralph was dying, Isabella was going to go to Gardencourt. Ozmond objects to her trip, but Isabella goes to break with him. Ozmond’s sister reveals a secret to Isabella: Pansy’s daughter Ozmond is not from her first wife, but from Madame Merle, although she does not suspect it. Pansy was born when Monsieur Merle was still alive, but he did not recognize the girl, and Ozmond wrote the story that his wife died during childbirth, although in fact she died childless. For six to seven years, Ozmond was Madame Merle's lover, then they broke up, but they are so much connected that they cannot do without each other. Having learned this story, Isabella is imbued with even greater pity and tenderness for Pansy, with whom her father and mother are ready to break life. Before leaving, she visits Pansy in the monastery, where she meets Madame Merle, who came to see the girl. Pansy does not like Madame Merle, and Isabella is once again convinced that for all her meekness, Pansy is not so simple. Pansy asks Isabella not to leave her, and Isabella promises her to return. Madame Merle opens Isabella's eyes to the fact that she owes her wealth to Ralph: it was he who persuaded his father to leave her a fortune. “I know you are unhappy. But I'm even more unhappy, ”says Madame Merle, Isabelle.

Isabella arrives in London, where she is met by Henrietta. She is going to marry Bentling and even, contrary to her convictions, intends to move to England. In Gardencourt, an aunt informs Isabella that Lord Warburton is getting married. Isabella only now understands how much Ralph loved her and says she is ready to die, just not to part with him. She asks Ralph if it is true that he made her rich. “I think I ruined you,” Ralph answers woefully. Isabella confesses to him that she is unhappy that Ozmond married her for money. After Ralph’s death, Goodwood arrives at Gardencourt. He persuades Isabella not to return to her husband, begs to stay with him. Isabella asks him to pity her and leave. Goodwood kisses her. Excited Isabella escapes into the house. When two days later, Goodwood arrives in London and comes to Henrietta in the hope of finding Isabella there, Henrietta informs him that Isabella left for Rome. Seeing his despair, she advises him to wait - after all, he is still young and he has time.