Lovely old time detective story.
I do love an old book. Written in 1958, post war in Japan, mostly a story about...sort of...trains.
I knew Japan was big on trains (similarly to the UK, it's our mode of transport), but reading about how they would plan their journey often sleeping overnight, upright, on the train to get from one place to another.
The crime is linked to trains and journeys and planning.
It's a nice, short enough, straightforward detective story that cross from one generation of detective (old, slow, "classic"), to young(er) and determined.
There are parts where I'm wondering what real evidence they have to follow up or chase down particular individuals, but it gets a pass being nearly 70 years old.