At seven o'clock on Jane's wedding day, Sophie arrives to help her dress. Jane wears the plain blond veil she has made herself, rather than the fancy veil that was destroyed by Bertha. In her wedding dress, Jane looks so different from her usual self that she seems a stranger to herself. As they drive to the church, Rochester looks grim, and Jane is so nervous that she doesn't notice whether the day is fair or foul. In the cemetery near the church, Jane observes two strangers and sees them again in the shadows of the church. When the clergyman is about to ask Rochester whether he takes Jane for his wife, a voice declares the wedding can't continue because of an "impediment." Rochester has another wife who is still living: Bertha Antoinetta Mason, a Creole woman he married fifteen years ago in Jamaica. Richard Mason appears, confirming this evidence, and Rochester admits that he had planned to commit bigamy.
Rochester commands everyone back to Thornfield to see his wife. Refusing to let go of Jane's hand, Rochester leads her up to the secret room on the third floor. They find Bertha groveling on all fours, running backwards and forwards like a beast. Her hair, wild as an animal's mane, hides her face. The woman attacks Rochester, almost throttling him, until finally he binds her to a chair.
Briggs surprises Jane by telling her that her uncle, John Eyre, had alerted Richard Mason to the marriage. John Eyre is a business associate of Mason's, so when Jane's letter arrived, announcing her engagement, he shared the information with Mason, who was resting in Madeira on his return voyage to Jamaica. John Eyre was dying and couldn't return to England to rescue Jane, so he sent Mason instead. Everyone leaves the attic, and Jane locks herself in her room. All her hopes are dead. In this moment of despair, Jane returns to God, silently praying that he remain with her.
Rochester's secret has been revealed. In the previous chapter, Bertha was merely an apparition; in this one, she becomes fully flesh and blood. An insane, Creole woman, Bertha represents British fears of both foreigners and women. Part human, part beast, Bertha is Jane's double, representing all of her rage and anger over the loss of identity the marriage promises to bring. Unlike Jane, who submissively gives in to Rochester's demands, Bertha refuses to be controlled; a woman whose stature almost equals her husband's, she fights with him, showing a "virile" force that almost masters the athletic Rochester. Finally, she is roped to a chair, much as Jane almost was in the incident in the red-room. Post-colonialist critics, such as Gayatri Spivak, have argued that Bertha, the foreign woman, is sacrificed so that British Jane can achieve self-identity, and the novelist Jean Rhys has written a novel called The Wide Sargasso Sea that presents Bertha's life in Jamaica before her madness. Both of these women writers suggest Rochester's relationship with Bertha wasn't as innocent as he claims; as a colonialist, he was in Jamaica to make money and to overpower colonized women. In the nineteenth-century, men had almost complete legal power over women, and perhaps this lack of power contributed to Bertha's madness, just as it caused Jane's temporary insanity in the red-room. These critics remind the reader that Jane Eyre isn't merely a story critiquing the social injustices against women, but also exposing the brutality of colonialism. In the previous chapter, Jane had joked about leading a rebellion of the women in Rochester's imaginary seraglio; now she has almost become a member of that harem, but Bertha leads the resistance.
Brontë's use of ice imagery in this chapter contrasts with the fiery images of the previous few chapters. In Chapter 25, for example, the wild wind and blood-red moon symbolized Jane's passion, but here all of that energy has drained away. Bertha's red eyes and virile force emphasize her excessive, crazy passions, but Jane has become a husk. Gone is the "ardent, expectant woman," and in her place is the "cold, solitary girl again." Jane imagines nature mimicking her desolation and chill: a Christmas frost has whirled through June, and "ice glazed the ripe apples, drifts crushed the blowing roses; on hayfield and cornfield lay a frozen shroud." All the world has symbolically become icy, frozen, snowy in sympathy with Jane's dead hopes. For Jane, the world has become a white waste, a chill, stark corpse that will never revive.