Set five thousand years in the future, planet earth has become a sparsely populated, arid wilderness. Most of the people have joined pacifist sects flying under the banner of heroes from the past who, they believe, fought off an alien invasion. One of these peace-loving sects is at odds with the others, adhering to the belief that the terrible conditions endured on earth are a result of human negligence. The remaining humans are an alliance of non-pacifist, non-believers who have been pushed to the desolate fringes of the habitable region. Aggression turns to war with the sects uniting in defence of what has become a reasonably good life. The dramatic climax reveals the truth of who was responsible for the apocalypse.