War left Earth a smoking ruin, but remnants of civilization survived by retreating in opposite directions. Some burrowed beneath the rubble, striving to maintain pre-War technology in underground enclaves. Others fled aloft aboard Windriders, massive airships fitted up as colonies in the clouds.Having learned a horrible lesson, and united by common need, the two groups are interdependent and nonviolent. Each survives by trading with the others, and cross-migration is common. But there is a hawk among the doves. The sole survivor of the forces that destroyed the world - the military windrider Shenandoah - has turned to piracy. Its commander takes no prisoners. Already Shenandoah has annihilated twenty-six of its fellows. much as the other Windriders abhor violence, a defense must be found. The alternative is death.