A biographer's obsession with a seventeenth-century alchemist triggers a supernatural intrusion that threatens his modern life. Matthew, a researcher focused on the enigmatic Nathaniel Shawcrosse, finds his reality fractured when the alchemist's long-dead mistress, Isabel, begins to manifest in the present. As Isabel seeks to reclaim her connection to the past through the body of Matthew's fiancee, Josie, the protagonist must navigate a terrifying psychological and physical encroachment. The narrative explores the thin boundary between historical fixation and present-day possession, forcing Matthew to confront the consequences of his academic curiosity.

This work is characterized by its blend of historical research and supernatural horror, focusing on the dangers of fixating on the past. The premise suggests a narrative that prioritizes atmosphere and psychological tension over conventional scares. Readers likely encounter a story that examines how the shadows of history can manifest in modern relationships. The pacing appears to be deliberate, allowing the sense of unease to build as the boundaries between the characters' identities begin to dissolve.