Coming in the wake of Murder of Roger Ackroyd, this book is a major disappointment. It is less of a novel and more of a collection of short mysteries tied by a thin thread. Like the other reviewers point out, the plot is highly unbelievable, and seems to be satirical of other crime literature.I am really glad Agatha decided to ditch Hastings in her latter novels. The running commentary provided by this latter-day Watson is redundant, distracting, and makes the whole thing look more like a story about the greatness of Poirot rather than a mystery that involves the reader. This whole book is too Sherlockian to begin with. There is much going about and doing action, despite the purported emphasis on sitting and thinking and psychology. True, some of it is in jest, such as the twin brother, but the shadow of Holmes is too dominant in this to allow enjoyment of Poirot as Poirot.