The first thing I noticed is that this book is typeset rather differently. The earlier ones had a somewhat distinctive look. This one is uchmore densely set and is thus a lot more words since it also comes in at a few more pages. Too many plot threads to tie up in the same number of words as the earlier ones, I think. This really works as a finale to a series. All the major plot points, personal and societal, come together in a nicely converging pattern and Compton’s ingenuity, diplomacy and fighting skills are all given a work-out here. There’s a mix of action on the trains, the train stations, another space station and a planet. Ancient tech, ancient crimes, revelations of past and present duplicity by individuals and races all come together in a satisying action-packed denouement.

My only problem is that one of the mysteries of “Trains in Space” was never solved. Sure, in the first book the explanation is given that it’s not the trains, tracks or tube that are the secret, but the coreline. However, this doesn’t really explain how the tube that encloses the coreline can be built over such huge distances (halfway across the galaxy). A bit of hand-waving is given where an apparent speed of 100 kmh compared to the tube translates to 1 light-year per hour “external” (relativity, schmelativity) speed (and no worrying about causality problems). But there’s no mention of any contraction of space occuring and a tube big enough to take sixteen train lines across tens of thousands of lightywars would need the mass of multiple star systems to complete. Still, this is Space Opera, not hard SF and so one just has to accept the background without delving too deeply and enjoy the story.