The novel focuses predominantly on the Athelstones, a family made rich through trade but who have recently joined the aristocracy, as a result of the patriarch, Robert, inheriting a baronetcy from his uncle. Unlike Robert, who is a generally benevolent character, Athelstone's second wife, Betsy, is a vindictive and covetous social climber, while his two daughters, Eliza and Clara, take after their mother and father respectively. Robert also has a son by his first marriage, Edmund, who is kind-hearted but somewhat too attached to the trappings of rank and wealth. In addition to the Athelstones, the novel follows the courtships and travails of a large cast of aristocratic and middle-class characters who are connected to the family in one form or another.
Following Robert's accession to the baronetcy, the family move from London to Exeter. There they are joined by Robert's niece, Rosetta, whose parentage has been cast in doubt, due to the denial on the part of her paternal grandfather, Lord Clifford, that her father and mother were ever married. Rosetta is treated cruelly by Lady Athelstone, but is defended by her uncle, Clara and Edmund. Rosetta is subject to the romantic attentions of a large quantity of suitors of varying degrees of inappropriateness, the worst being Lord Noel. Rosetta, however, is engaged to be married to Mortimer Vallancy, the son of an earl.
One evening, Rosetta is framed by Lady Athelstone, who (we later learn) has planted the key to Robert's safe in her sewing kit. Although Robert does not doubt his niece's innocence, she is nevertheless deeply disturbed. The same evening, she is abducted by Lord Noel's servant. After escaping, she resolves not to return to the Athelstones, fearing opprobrium, and assumes another identity, working first as an ammanuensis, then as a governess and finally as a schoolteacher. While in the latter post, she is discovered by her father, the Duke of Lavingford, and her friend, Lady Jane Conway. During that time, Mortimer has learned of Rosetta's abduction and writes her a letter in which he calls off the engagement. Later, after Rosetta's name has been cleared and her parentage established, she learns that Mortimer has been wounded in a duel, seemingly over another woman. She finds out later that he engaged in the duel in order to defend her honour. The two are wed. Lady Athelstone's various machinations are exposed and, following some harsh censure from her husband, she contracts brain fever and perishes, but not before repenting on her deathbed.
Ultimately, Rosetta learns that she is to inherit the wealth of her rich Uncle Peregrine, who has covertly observed the Athelstones for the larger part of the novel in the disguise of a servant called Umbell. The numerous other paramours of the novel are, by the conclusion, wed off, if they have not been already.

It has sociolects rather than really regional dialects. Lady Betsy Athelstone is the chief non-standard speaker in the novel. Her dialect does not appear to be regionally specific, but rather functions solely as a sociolect. Though ostensibly from London, her speech contains no stereotypically Cockney features, but instead lack of concord, metathesis ('purtest' for 'protest') and eye dialect. It also features some apparently northern elements, such as 'summat' for 'something'. Some interesting metalanguage concerning the attitudes of Lady Athelstone's daughters to her speech occurs on vol. 1, p.96.
The novel also features some Scots speakers (vol. 3), whose speech is marked predominantly by orthographical and lexical features. An old French dancing-master also appears (vol. 4), who code-switches between English and French, and whose English is marked by, among other features, v-w transposition and th-stopping.

Unexpectedly nondialectal characters: All of the servants speak Standard English. A fisherman called Tom Collett does not really speak in dialect, notwithstanding a few isolated solecisms.