A San Francisco horror writer becomes the target of a malevolent, centuries-old entity after witnessing a spectral figure mimicking his movements from across the city. Franz Westen, a man grieving his wife and struggling with sobriety, finds his quiet life upended when he notices a mysterious presence watching him from a distant hilltop. As he investigates the anomaly, he uncovers a hidden history of occult influence tied to famous literary figures like Clark Ashton Smith and Jack London. The narrative, presented through a blend of psychological realism and supernatural dread, forces Westen to confront the physical and metaphysical architecture of San Francisco as it transforms into a hunting ground for an ancient, parasitic force.

This novel is widely regarded as a seminal work of urban horror that effectively bridges the gap between classic weird fiction and modern psychological suspense. Readers and critics often highlight the author's ability to transform the familiar streets of San Francisco into a landscape of genuine unease and hidden danger. The inclusion of historical literary figures adds a layer of intellectual depth that distinguishes the narrative from standard genre fare. The prose is frequently praised for its meticulous attention to detail and its ability to sustain a sense of mounting dread throughout the story. It remains a significant entry in the author's bibliography for its unique fusion of personal trauma and cosmic terror.