This is the 3rd book in the Colony Ship Eschaton series.
Jamie and Michael continue to discover how vast and unknown the old ship is. Why do some of the artificial intelligence systems seem to work, but others do not? Who is the unknown that sent a dismembered body through the transport system? How will the refugees from Dome 17 interact with the people who were born inside the habitats of the Eschaton? What threats to the very survival of the people exist in the unknown reaches of the Colony Ship Eschaton? And personally, can Jamie and Michael survive these unknown threats?