Humanity faces its greatest challenge. The alien Reivers have conquered our planet, their newly erected strongholds casting shadows across a subjugated land. And this conflict has a bitter history.
The Reivers overran an alien homeworld in an interstellar war, but some of their victims escaped across space and found Earth. Seeking help, they brought humans to their ship in an effort to communicate. However, they'd unknowingly led the Reivers to us, who hunted them as they fled. Reivers now aim to destroy the alien spacecraft, transformed into the last refuge of free humans.
So Rachel Stewart will leave the habitat for a final, desperate, stand on the planet below. But the ship holds the key to salvation - and without it, humanity will be finished. The galaxy will be next.