Miss Mariana Porter lives in genteel poverty in Dublin with her father, a gamester and painter. They manage to get by but hope for something to come along to help them return to their old lives in London. Perhaps Mariana should accept the proposal of the Marquis, a friend of her father's. If only he hadn't proposed primarily in order to help Mr. Porter. When news of Lyndell Porter's Uncle Josiah Forrester's death, the Porter's hope that the city merchant's fortune will be theirs, but Forrester left his legacy largely to his nephew by marriage, Captain Brion Seymour. Mariana's friend Lucy writes that she's getting married in London and needs Mariana there as her bridesmaid, Mariana wonders if she should go. Then her long estranged Aunt Battledore comes to Dublin to whisk Mariana away to London where the girl enters Society. Mariana makes the acquaintance of Captain Seymour, whom she hates at first because of his newly acquired fortune and later because he is irritating. Captain Seymour is often seen on the arm of the beautiful but catty Lady Blanche. Then Mariana's solicitor makes a shocking announcement: Uncle Forrester left a third of his immense fortune to Mariana but only on the condition that she marry within the extended family or she'll forfeit everything. This leaves Mariana with three choices: Captain Seymour; his gentle poetic cousin Jeremy, a mute; and Tyger Dobyn, a pugilist. She likes Jeremy and even engages the help of a mutual friend, the sculptress Mrs. Damer, to teach her sign language. While Tyger is amusing, he isn't really the type a lady like Mariana should marry. Lucy counsels Mariana to choose one but Mariana refuses to marry without love. Mariana also learns some shocking secrets about her mother which may affect her future and possibly even her safety.