The narrative shifts to the party at Tantamount House, a grand London mansion designed by Charles Barry. The hostess, Lady Edward Tantamount, is holding a musical gathering in the building’s enormous central hall. As an orchestra performs Bach’s Suite in B minor, the guests react in various ways. Famous painter John Bidlake, Walter’s father, finds the event and the guests’ pious silence comical and whispers disruptive commentary to Lady Edward. Fanny Logan is moved to tears by the music, which reminds her of her late husband. Hugo Brockle admires the profile of Polly Logan from a distance, while John Bidlake is horrified to spot Mary Betterton, a former lover whom he now finds old and repulsive.

Upstairs in his laboratory, Lord Edward Tantamount, a reclusive biologist, is working with his assistant, a young, red-haired man named Illidge. The narrative recounts how Lord Edward abandoned a political career in his youth after a passage by Claude Bernard inspired him to devote his life to science. He and Illidge are performing an experiment that involves grafting tissue from a newt’s tail onto its leg stump to see if it will regenerate as a leg or a tail.

Lord Edward hears the Bach suite from the party below and, overcome by his love for music, insists they go downstairs to listen. Illidge is reluctant due to his shabby suit, but Lord Edward dismisses his concerns. Their arrival at the top of the main staircase is conspicuous. The sight of the huge, tweed-jacketed Lord Edward and his small, shabbily dressed assistant creates a stir among the formally attired guests. Embarrassed and made painfully aware of his class difference, Illidge stumbles on the stairs.

After the music concludes, the guests begin to socialize. John Bidlake takes his niece, Lucy Tantamount, to the dining room. There, they contemplate his famous painting, The Bathers, which evokes in Bidlake a melancholy awareness of his age and declining talent. They are interrupted by Mary Betterton, who engages him in a conversation about art and cynicism. Bidlake retorts that women have no souls, only bodies. Mrs. Betterton then laments the jadedness of modern youth. Elsewhere, Polly Logan and Hugo Brockle argue about the politics of Everard Webley, a fascist leader whom Hugo admires.

Lady Edward teases Webley, calling him a pirate king, and introduces him to an uncomfortable Illidge. After Webley leaves in annoyance, Lady Edward feigns interest in Illidge’s scientific work but quickly introduces him to General Knoyle and Colonel Pilchard. The two military men ignore Illidge, leaving him feeling resentful.

Walter arrives and searches for Lucy. He speaks with Frank Illidge, who launches into a bitter tirade against the idle rich, calling them insensitive and corrupt, and specifically condemns Lucy as a product of a decadent civilization. Meanwhile, Everard Webley tries to persuade Lord Edward to support his political movement, the British Freemen. Lord Edward is uninterested in politics and instead lectures an exasperated Webley on the depletion of the world’s phosphorus reserves. Lord Edward and Illidge then retreat to the lab.

Walter meets his editor, Denis Burlap, who is talking to Mrs. Betterton and seems oddly hostile toward him. John Bidlake and Lady Edward observe Walter from afar and discuss his “deplorable affair” (63) with Marjorie, whom Bidlake calls refined and imbecilic. The perspective shifts to Marjorie, who sits at home rereading Walter’s old, passionate love letters and grieves the loss of the gentle, considerate man he once was. Back at the party, John Bidlake suddenly feels ill. Lady Edward changes the subject to his daughter, Elinor, and her husband, Philip Quarles, who are returning from India.

In India, novelist Philip Quarles and his wife, Elinor, endure a final dinner with Mr. Sita Ram, an Indian nationalist. The heat, food, and conversation are unpleasant. On the drive back to their hotel, Elinor is stirred by the full moon and tries to reminisce about the early days of their marriage. Philip, lost in abstract thought, responds with detached coolness. Elinor accuses him of no longer loving her and of using his intellect as a shield against genuine feeling.

Philip reflects internally on his emotional solitude, acknowledging that Elinor serves as his essential interpreter—his “dragoman” (76)—for a world of human feeling he cannot access directly. Their car hits and kills a dog, and Philip immediately analyzes the event as a source for intellectual generalizations about morality and instinct. Elinor is horrified by his cold, intellectual response to the animal’s death.

At the party, Walter finally finds Lucy Tantamount. He watches as she intentionally provokes her acquaintance, General Knoyle, by praising his estranged stepson, Maurice Spandrell. As Walter and Lucy leave, the General’s wife, Mrs. Knoyle, secretly asks Lucy to arrange a meeting with Maurice for the next day.

In the taxi, Lucy kisses Walter and then pushes him away. He pleads with her, but she mocks his abjectness and digs her fingernails into his wrist. His passivity turning to rage, he kisses her savagely. She is surprised but not displeased by his aggression, and he tells her he will strangle her someday. When they arrive at Sbisa’s restaurant, Walter begs her to go somewhere they can be alone, but his return to a pleading tone restores her contempt. She ignores him and enters the restaurant. Back at Tantamount House, socialite Molly d’Exergillod tells Denis Burlap about Philip and Elinor Quarles and describes Lucy as a detached “fairy” (86). Lady Edward overhears and amends the description, calling her daughter a “leprechaun” (89).