Belinda is a beautiful, intelligent 17-year-old girl with an independent spirit and a formidable moral compass. Tasked by her matchmaking aunt to find a suitable husband, she observes the complex and often corrupt world of the wealthy elite. She acts as a grounded, discerning observer who trusts her own judgment over the shallow conventions of her peers, preferring to evaluate suitors and friends by their true character.

Lady Delacour is a witty, charming, and prominent socialite who outwardly commands attention at lavish parties. Behind her carefully choreographed manners, however, she suffers from severe depression and feelings of deep isolation. She harbors a dark secret regarding a neglected wound from a foolish duel, convinced that her physical condition is deteriorating rapidly.

Clarence is a handsome, confident, and somewhat arrogant young man moving through London's elite circles. Although initially driven by a desire to be universally admired, he reveals a protective and caring side when he teams up with Belinda to aid Lady Delacour. He carries a significant secret involving a young woman he keeps secluded at a country estate, an arrangement that sparks scandalous rumors.

Lord Delacour is a distant and reprobate nobleman who spends his time drinking and gambling. He lives a life of careless dissipation, rapidly depleting the family fortune. He remains entirely estranged from his wife and their only surviving teenage daughter, finding solace only in disreputable company.

Helena is the teenage daughter of Lord and Lady Delacour. Following the deaths of her two older siblings in infancy, she was sent away to boarding school and now resides with her aunt Margaret, entirely isolated from her immediate family. She possesses a gentle, cheerful disposition that contrasts sharply with her parents' misery.

Augustus is a wealthy, twentysomething, half-Creole plantation owner visiting from the West Indies. He is striking, confident, and possesses elegant manners. He quickly develops an intense affection for Belinda and proposes a formal arrangement, though he conceals personal struggles beneath his polished exterior.

Lady Percival provides a stark contrast to London's cynical socialites. She maintains a loving, tranquil home based on mutual respect and domestic bliss. She serves as a maternal figure to Belinda during a difficult period, offering thoughtful guidance on the nature of love, compatibility, and marriage.

Originally known as Rachel Hartley, Virginia is a strikingly beautiful young woman raised in total seclusion in the woods. After her grandmother's death, she is relocated to a remote cottage where she spends her time reading sentimental romances. Kept entirely separate from society, she lives in a naive, dreamlike state.

Lord Percival is a reliable, strong, and honorable man who shares a remarkably harmonious marriage with his wife, Anne. He actively participates in his family's peaceful life at Oakly-park, standing as a model of responsible masculinity.

Mrs. Stanhope is Belinda's well-intentioned but highly calculating aunt. Accomplished in the art of matchmaking, she has already successfully married off six other nieces and views Belinda's relocation to London strictly as a necessary step for securing wealth and social standing.

Marriott is Lady Delacour's fiercely loyal and obedient maid. She keeps a noisy exotic blue macaw as a pet and acts as a strict gatekeeper to her mistress's private rooms, actively participating in hiding Lady Delacour's physical decline from the rest of the household.

Philip Baddeley is a disreputable roué who runs with Hervey's initial social crowd. After Belinda firmly rejects his bold marriage proposal, he vindictively spreads damaging rumors about Hervey's secret life in an attempt to ruin his reputation and isolate him.

Doctor X. is a reputable, erudite physician known for his sagacity and professionalism. Belinda and Hervey urge Lady Delacour to consult him as an alternative to the unlicensed quack who has been keeping her medicated on opiates.

Mrs. Ormond is a woman of minimal education but impeccable character. She is employed by Clarence Hervey to be the live-in companion for Virginia St. Pierre, often coaxing the young woman to abandon her romantic daydreams and accept a practical marriage to her benefactor.

Margaret is Lord Delacour's sister. She lives near the Percival family and has taken on the responsibility of housing and caring for her teenage niece, Helena, providing the girl with stability away from her parents' toxic household.