If Children of Time was about survival, book 2 - The Children of Ruin - is about discovery. And Tchaikovsky shows discovery can be awe-inspiring, strange, bloody difficult, downright terrifying and deadly both on a personal and species-wide level. The book is filled with amazing feats of imagination and scientific extrapolation and - as with book 1 - Tchaikovsky creates a credible, alien mentality (not with spiders this time, but with octopuses and... something else) as well as keeping up the humour, terror and wonder that made Children of Time so enjoyable.