A series of mysterious, anonymous telephone calls reminding elderly residents of their impending mortality disrupts the social order of a London circle of friends. The protagonist, Dame Lettie Colston, finds her structured life as a penal reformer challenged by these unsettling intrusions, which force her and her peers to confront the reality of their aging. The narrative operates through a third-person perspective, weaving together the lives of various characters who are all linked by their proximity to death. The world is defined by the rigid social hierarchies of mid-century Britain and the physical limitations imposed by advanced age, creating a claustrophobic yet darkly humorous environment.

Readers and critics frequently highlight the clinical precision with which the author dissects the vanities and petty grievances of the elderly characters. Discussion often centers on the balance between the grim subject matter of death and the witty, detached tone that prevents the narrative from becoming overly somber. Many observers note that the book functions as a social commentary on the indignities of aging rather than a traditional mystery novel. The effectiveness of the world-building is often praised for its ability to capture the specific atmosphere of 1950s London society. Readers often find the interplay between the characters' past histories and their present decline to be the most compelling aspect of the work.