After discovering their parents were never legally married, two sisters find themselves disinherited and forced to navigate a hostile social landscape to reclaim their lost fortune. Magdalen and Norah Vanstone are thrust from their comfortable life into poverty, facing the rigid legal and social constraints of Victorian England. Magdalen, driven by a fierce desire for justice, adopts various disguises and schemes to manipulate the system, while Norah struggles with the moral implications of their situation. The narrative unfolds through a series of complex legal maneuvers and personal deceptions that test the sisters' bond and their resolve against a society that views them as illegitimate outcasts.

Readers and critics frequently highlight the novel's sharp critique of Victorian social conventions and legal injustices. Discussion often centers on the character of Magdalen, whose unconventional methods and moral complexity challenge traditional portrayals of heroines from the period. The pacing is noted for its intricate plotting, which keeps the reader engaged through a series of calculated risks and reversals. Many observers appreciate how the author balances the suspense of a mystery with a profound investigation into the nature of identity and legitimacy. The work remains a significant point of interest for those studying the evolution of the sensation novel and its impact on social discourse.