This book starts in London (the best place for a book to start, for me)
In a world after a war, with adults who were boys evacuated -and stranded on an island - like the boys in Lord of the Flies.
But it is a big world, so there are women in it, and people who are older, and younger than that.
At first it feels a bit like '1984' - the world is grey, England is suffering with the after-effects of war, there is austerity and terrible food.
But it goes in a different direction after that, it opens the world up wider - and it gets deeper into the characters' stories.
It concentrates on a variety of characters. I really like that each character has their own voice and point-of-view. Each one uses language differently, sees things differently, names things differently. So it is very easy to tell which one we are following.
(I have read books where this was not the case, and was confused and frustrated by them).
At a point 43% through the book, there are suddenly powered exoskeletons. Which are surprising and relevant to the plot.