Facing the prospect of his impending retirement, Hercule Poirot resolves to undertake twelve final cases, consciously mirroring the twelve legendary labours of the Greek hero Hercules. Poirot seeks to apply his meticulous deductive methods to these specific challenges, viewing them as a definitive capstone to his career. He faces a diverse array of adversaries, ranging from cunning criminals to complex social enigmas, all while navigating the rigid constraints of his own self-imposed moral and intellectual framework. The narrative unfolds through a series of distinct, episodic investigations that highlight the detective's unwavering commitment to order and logic.

This collection is widely regarded as a clever structural experiment that showcases Christie's ability to blend classical allusion with the traditional whodunit format. Readers often appreciate the thematic consistency that links the disparate cases, noting how the mythological framework adds a layer of wit to Poirot's final professional endeavors. The stories are frequently praised for their economy of prose and the sharp, concise nature of the puzzles presented within each chapter. While some critics argue that the short story format limits the depth of character development compared to her full-length novels, the consensus remains that the book serves as a sophisticated tribute to the detective's enduring legacy.