Fiction by Agatha Christie.
Continuing in my perusal of Agatha Christie's novel in order, I found this book to be up next. This is not one of my favorites, although it is still pretty good.
In this story, Poirot and Hastings are reunited, although Cpt. Hastings has married and moved all the way to South America. I suppose this means Mrs. Christie caved to pressure to bring the pair back, after she tried to retire Poirot in The Murder of Roger Ackroyd.
Anyways, as long as you manage to willingly suspend disbelief with some of the more fantastic elements, this is a fun mystery of the "master detective versus master criminals" variety.