Spoiler warning: to do justice to this book, I have had to mention more detail below than I would really have liked. So stop here if you don't want to know what happens.
Some books catch and hold your attention when you're reading them. I suppose those that don't aren't much use as books. This book does that, easily - and impressively, given that it is really three books, so it has to grab and hold you three times.
Some books also hold your attention after you've finished them, make you go back, perhaps re-read, and still keep you thinking. "Sputnik Caledonia" does that too.
In the first part, we meet Robbie Coyle, a young boy growing up in the Scottish town of Kenzie in the 1970s. He has a normal life - he is perhaps a little naïve, certainly imaginative, obsessed with spaceflight; he has two well meaning but slightly odd parents and a waspish older sister - and I found myself growing very fond of him. Had Andrew Crumey simply continued Robbie's story, that would have been quite enough for a decent and engaging book. In fact, Robbie has a very sad end - although we don't learn that for sure until part 3 - and instead of continuing the story, Crumey jettisons the careful portrait he has built up of 12 year old Robbie, and plunges into a 1984ish, Eastern-bloc style Scotland.
In Part 2 Kenzie has been replaced the The Installation, a closed area dedicated to scientific research and arms manufacture ("This is where we made the Bomb") which seems to have suffered a Chernobyl style disaster in the recent past. In this world, Robert Coyle, 19, a soldier, has "volunteered" for a hazardous duty, expected to be spaceflight. It is a nightmarish place, depicted absolutely convincingly.
This world is explicitly a warped echo of that in part 1, Wizard of Oz style ("we're not in Kenzie any more") with the same, or similar, characters reappearing in different roles. David Luss, the trendy lefty teacher, becomes Commissioner Davis, the Party enforcer (he keeps his smelly pipe). Mr Tulloch, Robbie's gentle, art inspired science teacher becomes Kaupff, head of the project Robert is part of (he keeps his interest in German romantic literature and philosophy as an organic part of science). Roaslind, the girl Robbie fancies from the TV programme "Top of the Form" becomes Kaupff's ruthless (and heartless) assistant. Robbie's mum and dad carry over, I think, to the couple he lodges with, mourning their lost son, and their daughter Miriam appears late in Part 3 (back in Kenzie) as (now MSP) Luss's partner. If she was in part 1 I missed her. This being (sort of) "The Wizard of Oz" there is of course a Dorothy who Robbie meet in Part 1, and a Dora who plays an important role in Part 2.
In spite of the book's title, the plan in Part 2 is to use Coyle as a human detector for "scalar waves" emitted by a black hole making a flypast through our solar system (the scientist who predicts these is called Hawkin, so they are Hawkin radiation...) To do this, he has to be isolated from both electromagnetic waves (ie placed inside a metal shell) and from gravity (in free fall - ie dropped from a bomber at high altitude). There are other unpleasant conditions I won't mention here. Being sensitive to these scalar waves, Robert seems, however, to have some spooky link to Robbie of Part 1, as he falls ill. In some way, Robbie and Robert are the same person, but in different worlds (split by an event in the 1800s), and they're in touch.
The end of Part 2 sees Robert plunging to his death (I think) as a dutiful servant of the Party. In Part 3, Robbie's parents, in present day Kenzie, fail to come to terms with the loss of their son and with the 21st century.
A mysterious stranger, who calls himself Robert Coyle, and says he is a "spaceman" is on a "Mission" to save the world, which has become split. To do this, he needs the help of "the kid", a streetwise 12 year old who chooses, in the end, to drop out of the plan, resulting in its failure.
Is this Robert the Robert from Part 2? Does "saving" the world mean replacing our world with the Part 2 alternate history? Where did the green glass marbles that Robbie picked up come from (were they made in The Installation, as Rosalind suggests, and somehow echoed in our world? Who are the "rebels" in the Installation? These are only a few of the more obvious questions left dangling.
Overall this is a baffling, engaging book, juggling literature, quantum mechanics and philosophy effortlessly. There are some hilarious vignettes, and a great deal of good observation - the ghastly installation is as well realised as Robbie's little world. (The unforced contrast between naive 1970s Robbie and the tough 2000s "kid" is especially good).
For me, the only bit that didn't entirely convince was Part 2 Robert. What is he really thinking - who does he really sympathise with? Is he really a loyal Party man or not? At times the character feels rather flat. On the other hand, it's clear that his mind has been seriously messed around, like Robbie he has been made ill and perhaps in the same way. So maybe the air of purposelessness to him is intended and natural.
This would, though, in any case be only the slightest of reservations. This book is excellent, the best I've read in a long while.