This book is the sequel to 2016's "Children of Time" a book I
enthusiastically squee'd about when I read and reviewed it on my
old website.

https://ascraeus.org/children-of-time-review/

As I said then "This is really good british science fiction,
thought-provoking and entertaining in equal measure." The sequel
just doesn't disappoint, hitting all the things which I so loved
in "Time".

I had very real concerns that the sequel would lack the impact
of the first book, the ending of the first was a complete
reversal, something I can't imagine anyone saw coming, and a
sequel would have to deal with those events in a meaningful way.
Tchaikovsky handles this transition brilliantly, neither getting
too bogged down in the existential crises nor ignoring them
completely as some lesser writers might. Instead those issues
permeate this book, as the Portiid and Human explorers are faced
with new unknown challenges.

Like the last book, this one uses multiple points of view.
Where the narrative of "Time" was split between Kern's World -
a terraforming experiment gone wildly, incredibly amok - and
the _Gilgamesh_ - an ark ship wending between the stars on a
centuries-long voyage - "Ruin" compacts the story into a single
star system, and is all the better for it.

That's not to say that "Ruin" is any less complex. That
single system is presented at differing timeframes, from the
commencement of a terraforming experiment to the final, vicious
climax of a conflict between the lifeforms discovered and
created by that experiment. Where we previously were confronted
by the alien intelligence of uplifted spiders, here we have
uplifted cephalapods, a species which has a distributed nervous
system, where consciousnes only partly resides in the brain.

The thing, the most incredible thing of all, is that this is
only the beginning of the complexity, the alienness, the voyage
into the unknown. Nothing I've said above spoils anything past
the first few chapters.

If I was to summarise this entire thing, then it would be
thusly:

IN the far future, superintelligent octopuses, superintelligent
spiders (who use ant colonies as a computer system) and their
Human allies all come together in an incredible adventure in a
richly tapestried, incredibly realised world.

I really can't recommend this book strongly enough, it is
*glorious*. I briefly met Adrian at the WorldCon in Dublin, and
now I wish I had read this beforehand. I am in awe of this man,
and his abilities.