A young governess arrives at a remote country estate to care for two orphaned children, only to become convinced that the grounds are haunted by malevolent spirits. Tasked with the welfare of Miles and Flora, the protagonist finds her authority challenged by the children's unsettling behavior and her own growing paranoia. As she attempts to shield her charges from the spectral figures she perceives, the narrative—presented through a complex, layered frame—questions whether the threat is external or a manifestation of her own deteriorating mental state. The isolation of the Bly estate serves as a claustrophobic backdrop for this struggle between protective duty and psychological unraveling.

This novella occupies a central position in the canon of psychological horror, frequently cited for its deliberate ambiguity. Critics and readers alike focus on the central debate regarding whether the ghosts are literal entities or projections of the governess's internal instability. The text is often analyzed for its sophisticated manipulation of perspective, which denies the reader a definitive resolution. Its enduring influence stems from the way it forces an active engagement with the narrative, ensuring that the horror remains rooted in the uncertainty of the human mind.