Convalescent Englishman Jon Forsyte, staying in Camden, South Carolina in 1924, meets Anne Wilmot at a picnic following a brief conversation about a lynching. Lost together in the pine woods, they shelter by an Indian mound, share confidences and growing intimacy. Jon then visits the Wilmot home, spends idyllic days with Anne, and on the last evening finally kisses her.
Elderson’s confession and flight over secret commissions precipitate a stormy shareholders’ meeting: Soames insists on disclosure, is assailed by the meeting and, refusing to “sing small,” resigns in anger and mortification. Michael uncovers Victorine’s modelling, calms the jealous Bicket, helps secure Fleur’s post‑nuptial settlement, and watches Fleur give birth to a son. The household steadies—Soames and Michael, reconciled in anxiety and relief, rehang the haunting white‑monkey picture.
In a sensational libel trial Marjorie Ferrar is relentlessly cross‑examined about her morals, refuses to answer questions about a past liaison, and the case becomes a public scandal. The fallout upends reputations: Marjorie breaks off her engagement, faces debts and—after promising her marquess grandfather to reform—considers the stage or emigration. Fleur and Michael are socially shunned; Fleur insists on escape, Soames undertakes to take her round the world, and Michael resolves to stay in Parliament, watching her depart.
Soames Forsyte tours Washington with his daughter and son-in-law, is disturbed on recognizing Jon Forsyte and fearing an encounter with Irene, and schemes to keep Fleur from being upset. He later sees Irene playing the piano in his hotel, is powerfully stirred by memory and his own ageing, then returns to his family, pretends to recover, and falls asleep.
Fleur engineers meetings with Jon and wins a passionate moment in the coppice, but Jon refuses to live in secrecy, tells Anne (who is expecting), and breaks with Fleur.
Distraught, Fleur’s recklessness leads to a gallery fire—Soames rushes in, saves many pictures but is struck by a falling frame and fatally injured.
Soames dies; Fleur, remorseful, keeps vigil while Michael undertakes to protect her and the family’s affairs.