A young governess arrives at a remote country estate to care for two orphaned children, only to find herself trapped in a web of psychological dread and potential supernatural influence. Tasked with the children's education and well-being, the protagonist soon perceives malevolent entities haunting the grounds. As she attempts to protect her charges, she struggles to distinguish between external threats and her own deteriorating mental state. The narrative unfolds through a first-person perspective, heightening the ambiguity surrounding the events at Bly Manor.

Discussion often centers on the persistent ambiguity regarding whether the ghosts are real or manifestations of the governess's fractured psyche. Readers frequently highlight the effectiveness of the author's prose in building a suffocating sense of unease without relying on overt violence. Critics often examine the text as a foundational work of psychological horror that challenges the reader's perception of truth. The balance between the domestic setting and the encroaching darkness creates a lasting impact that encourages multiple interpretations of the final outcome.