I have now gone through the first three of this series, and have made various comments about the characterisation and pace of previous books. All of these, barring the irksome superintendent are missing from this story, which has a background set against the then murky world of horse racing - in fact, other than the discovery of the initial body part on a train, this has little railway background at all. This one is a true whodunnit, though I did have a good idea who the criminal was, but there were enough red herrings and twists to make me wonder whether I was right, and then towards the end, even the superintendent came good as he started to shed his crusty image (at least for a while). In all, this is probably the best so far.