The gates to new worlds have opened and the first wave of settlers has already landed on a habitable planet they are calling Ilus, only to find a corporate colony ship arriving to claim the same ground under a UN charter. Holden is sent to mediate. Neither side wants mediation. Meanwhile something on Ilus is waking up. The most self-contained novel in the series, structured as a siege story on an alien world, with the highest environmental stakes of any book in the sequence.