Zillah leads Mr. Lockwood to an upstairs room that Heathcliff usually forbids anyone to occupy. Lockwood settles inside an old oak enclosed bed and notices names scratched repeatedly on the window ledge: Catherine Earnshaw, Catherine Heathcliff, and Catherine Linton. He then examines old books marked as Catherine Earnshaw's and finds childish diary-like writings in their margins.

The writings reveal an earlier life at Wuthering Heights after the death of Catherine's father. Catherine complains that Hindley has become a cruel master, that Joseph forces harsh religious observances on the children, and that Hindley and Frances treat Catherine and Heathcliff severely. A later entry shows Hindley degrading Heathcliff, forbidding him to eat or sit with the family, separating him from Catherine, and threatening to turn him out.

Lockwood falls asleep and first dreams that Joseph guides him through deep snow to hear the Reverend Jabez Branderham preach an endlessly long sermon. In the dream, Lockwood denounces Branderham, Branderham accuses Lockwood in return, and the congregation attacks with pilgrim's staves until the noise of a fir branch tapping the window wakes him.

Lockwood then dreams, while aware of the oak closet and storm, that he tries to stop the branch by breaking the window. Instead, he grasps an ice-cold child's hand and hears a voice calling itself Catherine Linton, saying it has been lost on the moor for twenty years and begging to be let in. Terrified, Lockwood wounds the apparition's wrist on the broken glass and screams aloud, drawing Heathcliff to the room.

Heathcliff is shaken by Lockwood's presence in the chamber and becomes violently emotional when Lockwood mentions Catherine. After Lockwood leaves, he overhears Heathcliff opening the window and begging Cathy to come in, revealing deep grief connected to the name Catherine. Lockwood retreats downstairs, where Joseph and Hareton appear coldly in the early morning, and he later witnesses Heathcliff abusing Zillah and the young Mrs. Heathcliff before dawn.

Lockwood refuses breakfast and leaves as soon as there is light. Heathcliff accompanies him partway across the snow-covered moor, where the paths are almost hidden and dangerous. After parting at Thrushcross Park, Lockwood loses his way repeatedly, finally reaches Thrushcross Grange at noon, and returns exhausted, chilled, and weak.