Inspector John Appleby navigates a series of intricate criminal puzzles, each requiring his sharp intellect to resolve. In this collection of twenty-three short stories, Appleby serves as the primary investigator, applying his deductive reasoning to various domestic and professional crimes. The narratives often feature high-society settings where hidden motives and social decorum mask illicit activities. The stories operate within the framework of the classic British whodunit, emphasizing logical deduction and the unraveling of complex alibis. Appleby must contend with deceptive suspects and convoluted circumstances to bring clarity to each case.

Readers frequently highlight the wit and intellectual rigor present in these short mysteries. Discussion often centers on the author's ability to condense complex plot mechanics into brief, satisfying resolutions. Critics note that the stories reflect the stylistic conventions of mid-century British detective fiction, prioritizing cerebral puzzles over visceral action. The collection is often praised for its consistency in tone and the sharp, observant nature of the central character. Many readers appreciate the variety of scenarios presented, which showcase the breadth of the author's creative range within the genre.