With Earth virtually destroyed, Bran Marshall flees to Rhea, a nearby planet now hostile towards "Earthers". Escaping onto a Rhean supply ship, he finds the crew slaughtered, with the only survivor a female warrior named Ohsha. As the two try to kill one another, the ship is damaged by meteorites. Bran and Ohsha must join forces to salvage the craft before it impacts the planet below — and the humans that live there.