Long ago, the Cyberat left Earth to co-evolve with machines. Now, led by the powerful dictator Castron, their Old Guard believe that machines should replace the physical body. But these beliefs are upended with the arrival of the human Polity - and their presence ignites rebellion.

Piper was raised as a weapon against the Cyberat, implanted with secretive hardware. When his parents are captured by the Old Guard, the Polity offer him unexpected aid. Piper knows the Polity want more from him, but at what cost? The rebellion also attracts the deadly prador, placing an entire world in peril.

As war rages across the planet, Piper must battle with the unknown technology implanted in his bones. It may be the Polity's answer to their relentless fight against the prador. It could also be civilization-ending Jain tech - or something far more extraordinary.