By 2106, the overpopulated, heated-up world's a mess. Disorder brings an oppressive "Brotherhood" to power in the northern hemisphere. The party believes in male superiority, the privileges of property, and dictatorial rule. Science has produced faster-than-light space ships, however. Jan Sussinissen, the son of a rebel leader, sneaks on board one such ship. He will pretend to scout a portion of an earthlike planet that troubled discoverers named New Start. The Brothers plan to implant there a feudal economy with Brotherhood bosses and serf-like, agricultural workers. Jan, in escaping, also hopes to infect such a society with civilized values. He lands in the forested north of the planet with a member of the Brotherhood. "Insect men," eight-foot creatures that jump like grasshoppers and climb trees, but can't swim or survive severe cold, immediately attack them. Gunshots don't stop the horrors, which strip Jan's companion of his flesh. Our protagonist escapes them by swimming to an island. There, he uses survival skills he acquired as a youth in his native Northern Canada. He builds a canoe and, finally, a cabin on an island in the far north. Jan struggles to reconstitute the technology developed by mankind over thousands of years. He figures out how to insulate a drafty log shelter, cure skins and make warm clothes, and how to concoct soap, vinegar, bread, smelting coke, and other essentials. Jan learns at a Brotherhood administrative center that fission explosives have been detonated in the ports of America and Europe. Also, the Senior Brother identifies him as a rebel "ringer." Thus, Jan must flee the center to avoid execution. Later, he returns for a short time to lead a rebellion of refugee serfs. Barbara Levy, a highly resourceful "entertainer," helps. After victory, a small cadre of skilled men and women join Jan at his homestead. In response to the nuclear attack, the Brotherhood drops fusion bombs on Mecca, Medina, Jerusalem, and Riyadh. Space-borne waves of Brothers who flee a convulsing earth recapture the center and re-enslave Barbara and other rebels. As a result of the bombing, earthquakes and volcanoes sprout in the subduction zones around the Arabian tectonic plate. A growing cloud of noxious fumes and basalt dust circles the globe, blanking out the sun. Before earth fully dies, rebels hijack space ships and, under the command of Jan's father, Hake, re-conquer the New Start administrative center. The insect men are evolving toward civilization. Conscious of the human threat, they swarm around the center, determined to eliminate the invaders. Jan, Barbara, and Hake organize a river-borne exodus of six hundred rebels and ex-serfs. Their destination is Jan's northern nucleus of a settlement. Another Brotherhood location is weakened by guilt over the demise of earth. After destroying most of its offensive ability, Jan returns to his settlement to prepare for the refugees. Attacked, he kills the leading Brotherhood official and his pirate crew. Jan has eliminated the authoritarian poison brought from earth. Still, the threat of the dominant native species remains. Several expeditions fight their way down river until the refugees encounter a driftwood dam swarming with thousands of insect men. Jan returns with a naturally occurring insecticide that clears the river and promises permanent superiority over insect men. After victory, Jan and his people celebrate a thanksgiving. They've successfully gained a new start for the last humans in the universe.