I totally failed to guess the killer!
Poirot was staple TV viewing when I was a teenage so the image of the character is burned well into my consciousness (thank you David Suchet) - so reading an Agatha Christie book tends to come with very easy imagination and even accents for characters.
The story is well built, told in a way that makes me think I should have been able to deduce the killer myself (and something I've always wondered about murder mystery stories) and does a good job of flipping my expectations on its head!
Solid stuff.
3 Highlights
Out of the tail of his eye he noted
If you dam the stream of natural behaviour, mon ami, sooner or later the dam bursts and a cataclysm occurs!'
That was stupid; but you are, if you will pardon my saying so, rather a stupid man!
Others I've read in the "Hercule Poirot" series: