When a seemingly ordinary woman is thrust into a high-stakes conspiracy, she must navigate a web of political intrigue to prevent a fascist coup. Nigel Strangeways' wife, Georgia, finds herself recruited for an undercover mission that demands she infiltrate a dangerous organization plotting to destabilize the government. As she adopts a new identity, she faces constant surveillance and the looming threat of discovery by ruthless adversaries. The narrative unfolds through a blend of suspenseful action and psychological tension, highlighting the precarious nature of her double life.

This novel is frequently cited as a departure from the traditional whodunit format, leaning heavily into the suspense-thriller genre. Readers often note the shift in tone compared to the author's other works, specifically regarding the focus on a female lead in a perilous espionage scenario. The narrative is characterized by its brisk pacing and the clever use of the 'ordinary person in extraordinary circumstances' trope. Critics and enthusiasts of the era's crime fiction appreciate the tension built through the protagonist's isolation and the constant threat of exposure.