The best mystery in the Poirot series. Though there were only 4 suspects, and the murderer was one of the four suspects, it really surprises you who it was. There were incredible twists and turns throughout the book. This is one mystery where not only Poirot , but three other individuals help him discover the criminal responsible for the murder of the Mephistophelean Mr Shaitana. Truly astounding.A must-read by the queen of crime.