Deathworld

Deathworld centers on Jason dinAlt, a professional gambler who uses his erratic psionic abilities to tip the odds in his favor. While visiting the planet Cassylia, he is challenged by a man named Kerk Pyrrus (an ambassador of the planet Pyrrus) to turn a large amount of money into an immense sum by gambling at a government-run casino. He succeeds and survives the planetary government's desperate efforts to take back the money. Bothered that he may finally have met someone superior to him, he decides to accompany Kerk to Pyrrus, despite being warned that it is the deadliest world ever colonized by humans.

There have been numerous supernovae in the region, meaning that planets in the area are rich in valuable radioactive ores, but Pyrrus is the only even marginally habitable one, and thus the only one that can support sustained mining operations. Pyrrus is no paradise. It has a gravity of 2 g; its 42° axial tilt creates severe weather; it has frequent earthquakes and volcanic eruptions; two large moons generate tides of up to 30 meters; and finally, there are high levels of radiation.

Everything on the planet is deadly to humans. The large animals are strong enough to destroy small vehicles, while the small ones have neurotoxic venom. Even the plants are deadly. All microorganisms consume insufficiently protected tissue as quickly as acids. On top of all this, life evolves so quickly that even Kerk and his Pyrran crew have to be retrained upon their return in order to survive.

Because of this harsh environment, the settlers are engaged in a ceaseless struggle to survive, which – despite generations of acclimation and a training regime harsher than that of ancient Spartans – they are losing. The money Jason won is used to buy desperately needed weapons.

While acclimating to the harsh planet, Jason turns his attentions toward solving the planet's mysteries and saving the faltering colony. The few surviving historical records show Jason that the settlers' numbers have dwindled since the planet was first colonized, and they are now restricted to a single settlement. Extrapolating backward, it is clear to Jason that the flora and fauna were once far less hostile to humans. Jason also learns of greatly despised "grubbers", humans living outside the city, with whom the Pyrrans grudgingly trade hardware for increasingly necessary food.

After several weeks, Jason leaves the city in search of the grubbers, who live in harmony with the harsh environment. They practice what many would consider suicidal forms of animal husbandry, with the assistance of their telepathic "talkers". Jason is able to earn their trust by demonstrating his own abilities. The outsiders' knowledge of the initial colonization effort is even more intriguing than that of the city dwellers. Not long after their arrival, animals suddenly began attacking the city, and have not stopped since. However, a number of colonists lived outside the city. Though they still found the planet incredibly harsh, they never suffered such attacks. The grubbers are their descendants. The two factions despise each other. The grubbers hate the city Pyrrans, or "junkmen", for cutting them off from space and refusing to trade food or ore for scientific knowledge or advanced technology, particularly medicine. The junkmen hate the grubbers for thriving while they are dying.

While studying the grubber community, he notices an anomaly—though the life-forms throughout the area are dangerous, they are nowhere near as lethal as the ones around the city. Some grubbers theorize that the initial schism was a disagreement over the city's location, in which the ancestors of the grubbers abandoned the dangerous ground in favor of their current homes. Jason has the grubbers guide him back to the city, so he can see it from the outside. There his psionic senses confirm his hypothesis. Every species of native flora and fauna is psionic, and all life around the city is telepathically "shouting" the same thing: "KILL THE ENEMY!" Pyrrus' biosphere is intentionally attacking the city.

Jason shares this information with the grubbers and wins their total support. They ask Jason to go back to civilization and return with a ship. In return they will reward him handsomely. Jason agrees, but only to get back to the city. He knows that though the grubbers would keep their word, the first thing they would get from civilization would be weapons with which to make war on the city. He has a better idea, and shares it with Kerk along with the truth about the attacks.

Jason builds a device that can track the intelligence giving commands to the native flora and fauna to attack the city, and puts it in the city's spaceship to search. They detect that the psychic commands emanate from a cave on an island far from the city. Jason prepares to go down and "talk" to what may be an alien intelligence, but the junkmen decide instead to attack and kill the intelligence. The resulting battle ends with hundreds dead, along with the intelligence after the entire island is destroyed in a nuclear blast. However, the attacks on the city grow even worse than before. Kerk blames Jason for the loss of the attack team (although the order to attack was given by him) and the futility of the plan and prepares to kill him. Jason is barely able to flee in an escape pod, but it is shot down by Kerk.

Jason crashes into the jungle and is stricken with a Pyrran infection. He awakens in the grubber village. The grubbers witnessed his escape and killed a junkman for his medkit to treat Jason. Then the village's "quakeman", who is precognitive, warns of an impending quake. The grubbers put Jason on a stretcher and follow the quakeman as he runs from the village, accompanied by just about every animal in the area. A tectonic event hits the village, flattening it. The animals flee together, without attacking each other.

Jason realizes the nature of the conflict. But he needs to tell everyone—grubbers and junkmen—at the same time. He plans an attack on the city, based heavily on the talkers. By stirring up an animal attack on the city opposite the spaceport they easily take the spaceship, and therefore the city. Jason is thus able to get the grubbers and junkmen into a room without them killing each other.

Jason now reveals all. Although all life on Pyrrus competes for survival individually, they react collectively to natural disasters. The grubbers, with the assistance of their talkers, have integrated themselves peacefully into the planet's ecosystem, killing only for food or in self-defense. The junkmen, however, think only of killing, and kill everything they can simply because they can. The animals and plants band together against the common threat and cooperate in trying to eliminate them, mutating to better kill humans. Jason proves this to the junkmen, first by having the grubbers safely handle one of the city's ultralethal species, then doing it himself. The city's science director pretends he is handling a training aid, and is able to do the same.

With this knowledge and the cooperation of both Pyrran communities, Jason offers a solution. As the prejudices between the two cultures are generations old, the two communities cannot simply merge. Instead, select junkmen will live among the grubbers to learn their methods of coexistence, and in exchange selected grubbers will be given transport on the city's only spaceship to restore their connection with the rest of humanity. Trade will be continued fairly, with the grubbers trading food and ore to the city Pyrrans for technology and medicines. The educational system will be completely redesigned around grubber survival techniques, after which the city's children will live in new lodgings outside the besieged city, which will remain home to those who cannot adapt to the wilds of Pyrrus. Though the city will inevitably fall to the onslaught, those who have adapted will no longer be grubbers or junkmen, but simply Pyrrans. Kerk and the leader of the grubbers make peace.

In Deathworld 2, Jason is kidnapped by the religious fanatic Mikah, who is determined to bring him back to the planet Cassylia, ostensibly to be tried for his various crimes but really (Cassylia does not want Jason returned, since his huge winnings have been spent and the planet has used the incident to promote the "honesty" of its casino) to help Mikah's religious movement to overthrow the government, which they consider corrupt. Jason forces a crash-landing on a planet where the human population has regressed. The technology is extremely primitive and knowledge is split up among many small clans, each one jealously monopolizing what it knows. Jason uses his ingenuity to survive, trading his knowledge for protection and power. He eventually allies with a clan which has the knowledge of electricity. He creates innovations and machinery for the clan, in the process devising a crude device that signals his location to a spaceship piloted by his Pyrran girlfriend, Meta.

In Deathworld 3, Jason invites those Pyrrans who cannot adapt to the changes on their home world to colonize "Felicity", a planet rich in mineral wealth, but home to humans who are divided into two primitive societies, reminiscent of early Asia. One is an agrarian society living in towns and cities; the other is composed of nomadic clans that constantly fight amongst each other, strongly reminiscent of the Mongols before they invaded China and settled down. The two are divided by an impassible, miles-high, continent-spanning cliff. Most of the warlike clans have recently been united under a wily leader calling himself Temujin.

Jason tries to infiltrate the warrior society and use his Pyrrans to wrestle the leadership of the clans away from Temujin, but is unmasked as an off-worlder and thrown down a deep cave. He survives the fall, landing in a bank of snow and finds that it is a passageway through the cliff. Jason changes his plans and contacts Temujin, who takes him for an unkillable demon. Jason offers the barbarian leader his greatest wish, to conquer the rest of the continent. Temujin does indeed prove unstoppable, but is perceptive enough to realize, at the peak of his triumph, that he has to pay an enormous price for what he has won, as his people are becoming corrupted by the easy life of civilisation and will forget their nomadic ways.

• Deathworld series listing at the Internet Speculative Fiction Database
• Review on goodreads.com
• Deathworld at Project Gutenberg
• Deathworld public domain audiobook at LibriVox