One of my favorite Christies. This one concerns an apparent serial killer who is killing his victims in alphabetical order - Alice Ascher in Andover, Betty Barnard in Bexhill, and Sir Carmichael Clarke in Churston. He also leaves a copy of a railway guide (an "ABC") by each body, and sends gloating letters to Hercule Poirot before each murder. Poirot enlists the help of the victims' survivors in his investigation. In an interesting twist, Hastings' narrative alternates with that of an omnipotent, third-person narrator ("Not From Captain Hastings' Personal Narrative") depicting a parallel story line involving a sad, mysterious man named Alexander Bonaparte Cust (ABC), who may or may not be the killer.

As always, Christie lays out the clues to the killer for the reader, but they're very easy to overlook. Just when you think you know the truth, you find out you're wrong. The story moves quickly without any lags and the characters are interesting.

One thing I find interesting is the belief that "Alexander" is a "bombastic" name. Apparently, it was out of fashion in the 1930s, which is when this book was published.