When a doctoral student makes the discovery of a lifetime, hardly anyone will believe her…until an alien starship arrives, requesting that ten thousand humans board and communicating through a strange pseudo-mathematical language that layers all five of the senses. Those who board the ship decode an enigmatic message: this Canon defines the divine will of the Makers.

One hundred years later, their descendants are at breaking point. They’ve built a city on a desolate ring orbiting Inworld, a dangerous Eden at the heart of the star system. With their resources running dry, the population is divided between those who want to give up, those who have put all their hope in a rescue mission from Earth, and those who want to travel to Inworld – a journey forbidden by the punitive laws of the Canon. Laws they’ve spent generations trying to translate. Laws enforced by merciless sentinels.

When possible intelligent life is detected on Inworld, an elite group is dispatched in secret. As the team cross its vast landscape, facing predators, homicidal superbeings, and titanic forces of nature, they all must follow one rule. Obey the Canon, or face certain extinction.

For all the danger their mission holds, it might just offer answers to their greatest questions too: answers to the Canon's mysteries, to who brought them to this treacherous world, and – most importantly – why?