The narrative opens in the sweltering convict settlement of Port Arthur, Tasmania, where Ensign Harcourt Lowther languishes in bitter discontent, attended by Francis Tredethlyn, an imperturbably cheerful private soldier. Tredethlyn’s serene disposition is rooted in his memories of a simple, laborious youth in Cornwall and his innocent affection for his cousin Susan, the daughter of a harsh, miserly farmer named Oliver Tredethlyn. While Lowther chafes against the stagnation of his life and dreams of his wealthy, beautiful fiancée Maude Hillary back in England, news arrives through an old newspaper that Oliver Tredethlyn is dead and has left his entire fortune—amounting to over thirty thousand a year—to his neglected nephew Francis. This sudden inheritance shatters Lowther’s equanimity, plunging the elegant officer into paroxysms of envy and despair, while Tredethlyn remains remarkably unmoved by his new wealth, caring only to discover the fate of Susan, who has been disinherited and driven from her home.
Buying his discharge, Tredethlyn journeys back to Cornwall and learns from the grim housekeeper Martha Dryscoll that Susan fled the farm years before to escape a forced marriage arranged by her father with a wealthy neighbor. Armed with this meager clue, Tredethlyn tracks his cousin’s vanishing trail to the bleak, unfinished Essex watering-place of Coltonslough, where he discovers she had found refuge as a nursery governess. Through a sheepskin-covered journal left behind by a charming, unscrupulous university man who called himself Robert Lesley, Tredethlyn uncovers a cruel deception: Susan was lured into a false marriage and heartlessly abandoned.
Meanwhile, Tredethlyn is drawn into the brilliant, dazzling sphere of the wealthy merchant Lionel Hillary and his daughter Maude at their river-side paradise near Twickenham. Although completely out of place among the fashionable loungers, Tredethlyn becomes the devoted shadow of the household, while the ambitious and calculating Julia Desmond—a impoverished Irish gentlewoman living as Maude's companion—systematically sets her toils to win the Cornishman and his immense fortune. Despite his awareness of Julia's machinations and his own hopeless, unspoken adoration for Maude Hillary, Tredethlyn allows himself to be drawn into an engagement out of a sense of misplaced gratitude and chivalry. As the narrative progresses toward its climax, the glittering world of the Hillarys begins to crumble under the crushing weight of a massive financial crisis.
Lionel Hillary, fighting desperately against impending ruin and public disgrace, faces total collapse. Maude discovers her father on the brink of despair, holding a weapon of self-destruction, and learns that twenty thousand pounds is all that stands between her family and utter annihilation. The story weaves these converging fates together, examining how different souls bear the burdens of sudden riches, lost innocence, and impending catastrophe.
