Solomon has passed judgement.

The AI has chosen his ideal humans for Project Nomad, mankind's first extrasolar colony on Opis, forty light years from an Earth ravaged by more than a century of disease, famine, and war. Now his band of soldiers, farmers, and scientists have one final chance to launch the Ainatio corporation's ageing interstellar ship, Shackleton, and join the crew of Cabot at Nomad Base.

They have a deal. The Alliance of Asian-Pacific States, Earth's last surviving superpower, will let the launch go ahead in exchange for the instant communications research that made Nomad possible. But an unknown informer betrays a deadly secret: Solomon is the sole survivor of a banned class of AIs that were shut down after causing millions of human deaths. APS can't allow him to escape. They have to stop the launch and destroy him as well. But Solomon is ready to go to war to complete his mission.

While the situation on Earth spirals out of control, Captain Bridget Ingram is doing a deal of her own with newly-discovered neighbours on Opis. The alien crew of a warship have offered to share a technology that'll change the future of humanity. But they want something in exchange: protection.

The aliens haven't told Ingram the whole story, though. She's going to find out very soon who they need to be protected from, and why. It's too late to stay neutral and too late to abort the mission. If she doesn't take the biggest gamble of her life - one that could destroy the fledgling colony before it's even begun - the rest of the colonists will never make it to Opis.

Nomad has to succeed. Humanity's future will depend on it.