I'd never read any of Ken MacLeod's books before so wasn't sure what to expect (and I don't know if this one is typical). But I did find it absorbing, thought provoking and entertaining. I don't want to give away too much of the plot, but it consists of two greatly contrasting elements - one might say universes. Precisely how they are linked,what is real, and what isn't, is hinted at but not made clear until the end (and I'm not sure even then if you can be completely sure).
Most of the book describes Lucy's (a young woman working for a games developer in Edinburgh) experiences as she is sucked into a bizarre conspiracy which combines the politics of the Caucasus (this is in 2008, the year that tension between Russia and Georgia spilled over), family history, smuggling and the CIA. This is a fast moving strand and there is a good contrast drawn between the stoically ordinary Lucy (who has, though, a dramatic past) and a strange gallery of figures (some relatives) who appear to overturn her life. I was reminded a bit of the setup of a John Buchan novel (though the politics are much further Left). Perhaps the only jarring note here is how readily Lucy agrees to drop everything and go off on a quixotic mission in Krassnia, the Caucasian republic at the centre of things. But that may be explained in the denouement (difficult to say more without giving things away). "Restoration", it turns out, is a theme throughout the book, with a number of different levels of meaning.
But this is more than an action thriller. Framing the book is a different perspective, which recurs here and there in the main narrative, not being resolved until the very end. You can then go back and read the opening section with a completely different level of understanding.
It's all very deftly done, and if this is typical of MacLeod's work, I need to do some catching up with his earlier books. I'd be grateful suggestions about where best to start!