Masterful. It’s a classic for a reason: a locked-room mystery on an entire train, that builds slowly through lie after lie until the truth comes rushing out all at once.
Damn, but Christie was good.
Three things I learned about writing:
- Skip over the dialog that doesn’t matter. Sometimes it’s enough just to say “so-and-so made a suitable response.”
- Even adventures that get stumbled into have to be driven by the protagonist’s choices. Poirot doesn’t ask for the mystery, but he deliberately pursues it to the end, because that’s who he is.
- Put the description at the start of the scene, briefly. If the position of something isn’t important, leave it out. It’s enough to report that “there were pencils and paper,” we don’t always need to know exactly where everything is.