After Catherine Linton’s death, winter weather descends on Thrushcross Grange, where Nelly tends the frail newborn while Edgar remains shut in grief. Isabella Heathcliff suddenly arrives from Wuthering Heights, soaked, injured, exhausted, and laughing from shock. She insists on leaving at once for Gimmerton rather than staying near Edgar, fearing Heathcliff will pursue her to torment her brother.

Once warmed and bandaged, Isabella explains that she has escaped because her hatred of Heathcliff has finally overcome her fear. She describes the days after Catherine’s death: Heathcliff has been absent or locked away in grief, repeatedly going toward the Grange, while Hindley grows sullen and drunken. During a storm, Hindley locks Heathcliff out and tries to organize an ambush, but Isabella warns Heathcliff rather than become party to murder.

The confrontation turns violent when Heathcliff forces his way in, disarms Hindley, and brutally beats him while preventing Isabella from calling for help. Joseph threatens to report the matter to Edgar, but Heathcliff compels Isabella to confirm that Hindley began the attack. The next day Isabella deliberately taunts Heathcliff about Catherine and about his cruelty, and Heathcliff wounds her by throwing a knife; she escapes across the moors to the Grange.

Isabella refuses Nelly’s pleas to stay, kisses Edgar’s and Catherine’s portraits, and departs permanently. Nelly later explains that Isabella settles near London, gives birth to a sickly son named Linton, and maintains correspondence with Edgar. Heathcliff learns of the child and declares that he will claim him when he wants him, though he leaves Isabella undisturbed until her death years later.

Edgar is relieved that Isabella has left Heathcliff but withdraws almost completely from public life, giving up his magistrate duties and living in seclusion with visits to Catherine’s grave. His grief softens through devotion to his daughter, whom he calls Cathy. Nelly contrasts Edgar’s faithful endurance with Hindley’s despair and self-destruction.

Within six months, Hindley dies drunk and deeply in debt. Nelly goes to Wuthering Heights to arrange a respectable funeral and learns that Heathcliff holds the mortgages on the entire estate. Heathcliff keeps possession of Wuthering Heights, prevents Hareton from being taken to the Grange by threatening to claim Linton in exchange, and leaves Hareton ignorant, dependent, and reduced to servant-like status in his own inheritance.