A chance encounter with a mysterious woman in white on a moonlit road sets off a complex chain of events that threatens the lives and sanity of those involved. Walter Hartright, a drawing master, accepts a position at Limmeridge House, where he discovers a striking resemblance between his pupil, Laura Fairlie, and the distressed woman he encountered in London. As he becomes entangled in the lives of the household, he faces opposition from the manipulative Count Fosco and the enigmatic Sir Percival Glyde. The narrative employs an epistolary framework, utilizing multiple perspectives and legal documents to reconstruct the events surrounding a conspiracy involving identity, inheritance, and institutional confinement.

Readers and critics frequently identify this work as a foundational text in the development of the sensation novel genre. Discussion often centers on the effectiveness of the multi-perspective narrative structure in creating suspense and maintaining ambiguity throughout the plot. Many observers highlight the psychological depth of the antagonist, Count Fosco, as a significant element that elevates the tension beyond standard mystery tropes. The atmospheric descriptions of the English landscape and the claustrophobic nature of the domestic settings are often cited as key contributors to the book's enduring appeal. Scholars and casual readers alike note the precision with which the author critiques the legal and social limitations placed upon women during the nineteenth century.