I must confess that I have tried to read all of Agatha Christies novels with Hercule Poirot as the main detective. Of all these, this is my favourite, for a number of reasons. I agree with a fellow reviewer, that Poirot is at his best, and most interesting, when Catain Hastings is on board. The synophis is that behind the Worlds diasters/affairs are four people. Poirot takes them on, with a LITTLE help from Hastings. The inclusion of Hastings is a masterstroke by christie, as we see events through his romantic, simple mind, and he addresses points/questions that would often would love to yell out to poirot.This is Boys own stuff, and is riveting to see Poirot stretched to combat this mysterious sect. Great read