I always enjoy Greg Egan’s writing. Coupled with his scientific background and fertile imagination, he manages to come up with places and aliens unlike any others – read my review of his amazing The Clockwork Rocket, the first book in the Orthogonal series.
Seth is a surveyor, along with his friend Theo, a leech-like creature running through his skull who tells Seth what lies to his left and right. Theo, in turn, relies on Seth for mobility, and for ordinary vision looking forwards and backwards. Like everyone else in their world, they are symbionts, depending on each other to survive.
In the universe containing Seth’s world, light cannot travel in all directions: there is a “dark cone” to the north and south. Seth can only face to the east (or the west, if he tips his head backwards). If he starts to turn to the north or south, his body stretches out across the landscape, and to rotate as far as north-north-east is every bit as impossible as accelerating to the speed of light. Every living thing in Seth’s world is in a state of perpetual migration as they follow the sun’s shifting orbit and the narrow habitable zone it creates. Cities are being constantly disassembled at one edge and rebuilt at the other, with surveyors mapping safe routes ahead. But when Seth and Theo join an expedition to the edge of the habitable zone, they discover a terrifying threat…
In order to be better able to visualise this world, my firm advice is to visit Greg Egan’s site at the link:
where you can discover how he came up with this intriguing creation and the inhabitants. Alongside all the maths, the world is also more fully explained before you plunge into this one. Inevitably, I discovered the site after I had completed the book and although I had picked up the gist of what was going on, it would have been helpful to have understood more of the complexities of the world and this remarkable indigenous species as I was reading it. However, if this story was simply about an enjoyably weird world and creature with little story or dry-as-dust descriptions bulking up the book – while I would doubtless have something enthusiastic and polite to say about Egan’s extraordinary imagination, I wouldn’t be nearly as excited about this one as I am.
For not only does Egan offer a unique world and alien race – he also provides a cracking adventure story full of tension and excitement right from the start through to the climactic ending. I quickly bonded with Seth and his parasitic companion Theo and enjoyed the tensions and teamwork evident in their linked partnership. What happens if the Walker host has a major quarrel with his Sider? This premise is also explored within the story. I stayed up far later than I should to find out what happens to this embattled species as Seth and Theo struggle to discover a river big enough to support the large city where he was born and bred.
I love this one. Brilliant and inventive, this book reminds me all over again just why I love science fiction so much…