Later that evening, Jane lies in bed, gazing at the moonlight coming in her window. Suddenly, she hears a heart-stopping cry for help. Jane hurriedly puts on some clothes, horror shaking her body. All members of the party have gathered in the hallway, wondering if the house is on fire or if robbers have broken in. Rochester assures them that the noise was simply a servant having a bad dream and sends them back to their beds. Jane knows this is a lie, because she heard the strange cry, a struggle, and then a call for help. Before too long, Rochester knocks on her door, asking if she can help him, as long as she isn't afraid of blood. Together they climb to the mysterious third story of the house.
There they discover Richard Mason with a bloody arm. Rochester asks Jane to sop up the blood while he runs for the surgeon, but insists that Mason and Jane not speak with each other; if they do, Rochester will "not answer for the consequences." Jane stares at a cabinet in the room, which bears a grim design: the twelve Christian apostles with a dying Jesus hanging from a cross above them. As dawn approaches, Rochester finally returns with the surgeon. While he dresses Mason's wounds, the men speak obscurely of the woman who bit and stabbed Mason. Rochester has Jane run downstairs to find a special cordial he bought from an Italian charlatan. He measures twelve drops of the liquid into a glass, and has Mason drink the mixture, which Rochester claims will give him the "heart" he lacks for an hour or so.
After Mason has left, Jane and Rochester walk through the gardens. Rochester tells Jane the hypothetical story of a wild boy indulged from children, who commits a "capital error" while in a remote foreign country. He lives in debauchery for a while, then seeks to resume a happy, pure life with a kind stranger, but a "mere conventional impediment stands in his way." What would Jane do in such a situation, Rochester asks? Jane's answer is that a sinner's reformation should never depend on another person; instead, he should look to God for solace. Rochester then asks Jane, without parable, if marrying Blanche would bring him regeneration? He describes Blanche as a "strapper," big and buxom, like the women of Carthage, then rushes off to the stables to speak with Dent and Lynn.
The secret residing on the third floor of Rochester's house is becoming ever more difficult for Rochester to disguise. Rochester's feelings are apparent through his description of his house; while for Jane it is a "splendid mansion," for Rochester it is a "mere dungeon," a Bridewell. While she sees only the glamour of the place, he sees the gilding as slime, the silk draperies as cobwebs, the marble as "sordid slate." Jane is unable to see below the surface to the secret residing within Rochester's domestic space. Under a veneer of domestic tranquility lies a monstrous secret — in the form of the strange woman who lives on the third floor. As Jane notes, this crime or mystery is one that can be neither "expelled nor subdued by the owner," emphasizing Rochester's inability to control this woman. Descriptions of her — she "worried me like a tigress" and "she sucked the blood: she said she'd drain my heart" — suggest her ferocious power and vampiric tendencies. Bertha seems to represent a silent rebellion brewing in women's minds, one Jane will discuss later in the novel.
Jane Eyre combines the techniques of several literary genre, including the bildungsroman (a novel that shows the psychological or moral development of the main character), the romance, and the gothic novel. Elements of gothic predominate in this chapter. Generally, gothic uses remote, gloomy settings, and a sinister, eerie atmosphere to create a feeling of horror and mystery. Jane's language in this chapter — filled with references to the supernatural, mystery, crime, secrets, and excessive emotions — fits this rubric. For example, Jane's description of her experience on the mysterious, remote third story of the house contributes to the reader's sense of horror and impending mystery: She tells of the "mystic cells," of "a pale and bloody spectacle," of a mystery that breaks out "now in fire and now in blood, at the deadest hours of night," creating a "web of horror." Her portrait of the grim cabinet depicting the twelve apostles, on which she imagines Judas "gathering life and threatening a revelation of Satan himself," suggests a devilish, supernatural evil. Similarly, Rochester's ability to conjure up a cordial to give Richard almost supernatural strength, hints at his mysterious, possibly unnatural powers.