The Mystery of the Blue Train - Misteri Kereta Api Biru

Her puzzles are legendary, but I wonder how much planning went into the placement of red herrings versus genuine clues.

The way class distinctions played into motives made the story feel richer. Did this make anyone else suspect certain characters more?

The confined space creates such a tense atmosphere. I'm curious whether Christie was influenced by real train journeys or simply loved the idea.