As the rivalry over who will take Lizzie's hand in marriage intensifies, Lizzie flees. Meanwhile, the once-kindly Mr. Boffin has become a tyrant to Rokesmith, who evokes the sympathy of the formerly haughty Bella.
Two low-life characters sifting through the dust mountain have found an alternate will from old Harmon, which they plan to use to blackmail Mr. Boffin. Rokesmith and Bella have secretly married, without Bella realizing her husband is actually John Harmon, her original fiancé.