"Five Little Pigs" by Agatha Christie. Observe how Poirot finds the truth behind a murder that happened long ago.
The title is a reference to the nursery rhyme "This Little Piggy", which form the basis for the five main characters in this story: a bold businessman, a timid herbalist, a spoiled lady, a stern governess, and an adventurous lady who contradicted the statements from the other four characters. The characters are developed with a fine attention to detail, and it's interesting to see how Poirot adapts different strategies in dealing with each personality. These characters are partially what makes this novel good.
The distinguishing feature of this novel is the steady and even pace which the events are presented. The detectives in most other murder mysteries often have a seemly advantage over readers in that they get to collect and interact with the evidences first hand, so perhaps they should have an easier time in solving those cases. This particular book is clever in that it places Poirot on the same footing as the readers, working mostly from inaccurate and biased accounts from eyewitnesses. While Poirot did have some opportunity in extracting additional confirmations after reading the written accounts, the solution is mostly based on theories that would be consistent with all the personalities. In this sense, this novel feels more "fair" to the reader, which is what makes it great.
There was only so much that Poirot can do for a case that took place long ago, but there was still closure in the end. It was a pleasure to read this uniquely leisurely paced murder mystery.
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