Lockwood becomes sick after his traumatic experience at Wuthering Heights, and—as he writes in his diary—spends four weeks in misery. Heathcliff pays him a visit, and afterward Lockwood summons Nelly Dean and demands to know the rest of her story. How did Heathcliff, the oppressed and reviled outcast, make his fortune and acquire both Wuthering Heights and Thrushcross Grange? Nelly says that she does not know how Heathcliff spent the three years that he was away and that it was at this time that he apparently acquired his wealth. But she agrees to continue with her tale.
About six months after Catherine’s marriage to Edgar Linton, Heathcliff returns home, surprising Nelly at Thrushcross Grange. When he comes indoors, Catherine becomes almost giddy with happiness at the sight of him, and their obvious affection for one another makes Edgar uncomfortable and jealous. Heathcliff has grown into a polished, gentlemanly, and physically impressive man, though some hint of savagery remains in his eyes. He announces that Hindley has invited him to stay at Wuthering Heights. This surprises both Catherine and Nelly, but Heathcliff tells Catherine that when he sought Nelly at Wuthering Heights earlier that day, he came across Hindley in a card game with his rough friends. Heathcliff joined them in the gambling, and, because his reckless bids seemed to bespeak a great wealth, Hindley excitedly invited him to return.
Catherine and Isabella begin to visit Wuthering Heights quite often, and Heathcliff returns the favor by calling at the Grange. Isabella begins to fall in love with Heathcliff, who, despite his obvious love for Catherine, does nothing to discourage her sister-in-law’s affections. Nelly suspects that he harbors wicked and vengeful motives, and vows to watch him closely.
Nelly travels to Wuthering Heights to talk with Hindley, but instead she finds Hareton, who throws stones at her and curses. Nelly learns from Hareton that Heathcliff has taught the boy to swear at his father, Hindley, and has forbidden the curate, who offered to educate Hareton, to set foot on the property. Heathcliff appears, and Nelly flees.
The next day, at the Grange, Nelly observes Heathcliff embracing Isabella. In the kitchen, Catherine demands that Heathcliff tell her his true feelings about Isabella. She offers to convince Edgar to permit the marriage if Heathcliff truly loves the woman. Heathcliff scorns this idea, however, declaring that Catherine has wronged him by marrying Edgar, and that he intends to exact revenge. Nelly informs Edgar of the encounter occurring between Catherine and Heathcliff in the kitchen, and Edgar storms in and orders Heathcliff off of his property. When Heathcliff refuses to leave, Edgar summons his servants for help. However, Catherine locks herself and the two men inside the kitchen and throws the key into the fire, forcing Edgar to confront Heathcliff without the help of additional men. Overcome with fear and shame, Edgar hides his face. Still, Catherine’s taunts goad Edgar into striking Heathcliff a blow to the throat, after which Edgar exits through the garden. In terror of the larger and stronger Heathcliff, Edgar hurries to find help, and Heathcliff, deciding that he cannot fight three armed servants, departs.
In a rage, Edgar declares that Catherine must choose between Heathcliff and himself. Catherine refuses to speak to him, locking herself in a room and refusing to eat. Two days pass in this way, and Edgar warns Isabella that if she pursues Heathcliff, he will cast her out of the Linton family.