The ABC Murders by Agatha Christie is a clever detective story featuring Hercule Poirot.

A mysterious killer known as “ABC” is murdering people in different towns — in alphabetical order — and leaving an ABC railway guide at each crime scene.

Poirot races to stop the killer, who seems to be taunting him personally. In the end, it’s revealed that the murders were a cover-up for one personal killing hidden among the rest.