The Mystery of the Blue Train is a typical Poirot mystery, just not presented in her signature intriguing style. There are just too many shifts to the points of view of the supporting characters. The clues are perceivable, but they aren’t backed by any information that is revealed earlier. There were many moments when I knew what was being narrated was important, was a clue to something. But I could just not put my finger on why that was so. The resolution towards the end too did not feel very natural; it felt rushed, forced.
With the way the novel is structured, it felt as if Christie began writing this somewhere in the middle when Poirot is introduced, reached towards the end, and began to wonder how to tie the woven mystery up. All the side characters and their backstories were penned at that point and spread across the novel.
As a whole, the story just didn’t feel coherent. It wasn’t boring; I don’t think Christie can write a boring mystery. But it just wasn’t one of her finest works. I have heard even she has acknowledged this fact.