The story begins with the small human resistance that exists on what remains of the Commonwealth worlds attacked by the Primes. Human resistance forces have found two ways to fight back: using the Prime weapons (primarily directed-energy weapons) against the invaders, and disrupting communication between the slave caste (motiles) and the commanding caste (immotiles) of the Primes. Meanwhile, the humans in the remaining Commonwealth pursue other plans: to develop a set of weapons and warships to defend against the next Prime invasion and force the conflict back into Prime space; to develop a "quantumbuster superweapon" based on technology supplied, unbeknownst to most humans, by the Starflyer; and to prepare for the evacuation of known space altogether if necessary.