Je vous assure, Hastings - there is nothing so dangerous for anyone who has something to hide as conversation! Speech, so a wise old Frenchman said to me once, is an invention of man's to prevent him from thinking. It is also an infallible means of discovering that which he wishes to hide.

This was one of the first Christie novels I've ever read, and boy did it survive after the re-read! I very much enjoyed the experience of reading this already knowing who the killer was, because then I could capture the subtle hints that were strewn through the book. And they ARE subtle, but they are there and when you get to the explanation part of the finale, it makes perfect sense! That is the magic of Agatha Christie's books for me - the final reveal is extraordinary, but it makes sense and is perfectly explained because the clues were there all along! Also, I love how she is able to misdirect our attention and play us, readers, for a fool (I love when I'm absolutely fooled in a mystery novel!).
And let me say, this particular installment in the Poirot mysteries is so good that not even Hastings (which is a character I deeply dislike, especially when he's the narrator) couldn't ruin it for me. I just wish that Dame Agatha would've written more serial killers in her works, because the whole 'who will he kill next', the chase, the letters, just had me turning the pages and wanting to read more!