The novel opens with the origins of Evelina, an orphan brought up in secluded retirement by the benevolent Mr. Villars. Shielded from the world, she possesses virtue and natural charm, but completely lacks knowledge of societal forms and manners. At seventeen, an invitation to visit London and Brighton introduces her to the bustling world of assemblies, plays, and operas.
Her beauty immediately draws attention, most notably from the noble and refined Lord Orville, whose manners and intellect deeply impress her. However, Evelina's lack of worldly experience leads to numerous social blunders, such as inadvertently refusing one partner at a ball and accepting another, which provokes the mockery of superficial dandies like the arrogant Mr. Lovel and the aggressive Sir Clement Willoughby.
Compounding her social difficulties is the sudden appearance of her vulgar and litigious grandmother, Madame Duval, along with some uncouth city relatives, the Branghtons. Their coarse behaviour and constant quarrels constantly mortify Evelina and threaten to expose her to public ridicule. Despite these embarrassing encounters, Evelina's innate grace and genuine kindness gradually win the admiration of those around her, including Lord Orville, who actively protects her from insults. As the narrative progresses, the shadow of her estranged father, the aristocratic Sir John Belmont, looms large, raising questions about her rightful inheritance and social standing. The plot develops through a series of chaotic social outings, misunderstandings, and humorous misadventures orchestrated by the boisterous Captain Mirvan, testing Evelina's resilience and judgment. Ultimately, the story builds toward a resolution concerning her family lineage, her mother's tragic history, and her growing attachment to Lord Orville.
