This anthology presents a curated collection of supernatural tales that explore the thin boundary between the mundane world and the encroaching unknown. Each story functions as a self-contained narrative, focusing on protagonists who encounter inexplicable phenomena, psychological unraveling, or spectral visitations. The collection utilizes a variety of narrative frameworks, ranging from Victorian gothic sensibilities to early twentieth-century psychological realism, to challenge the characters' perceptions of reality. These individuals must navigate environments where logic fails and the environment itself becomes an active, often hostile, participant in their undoing.

This anthology is regarded as a significant entry in the long-running Fontana series, which served to preserve and popularize classic ghost fiction for a mid-century audience. The selection reflects Robert Aickman's distinct editorial eye, favoring stories that prioritize mood and existential unease over traditional jump scares. Readers often highlight the inclusion of May Sinclair and Vernon Lee as evidence of the collection's literary depth and historical importance. The volume remains a touchstone for those interested in the evolution of the supernatural short story format throughout the twentieth century.