Doctor Avrana Kern spearheads an Exaltation Program to seed a terraformed world with primates guided by a nanovirus. A Non Ultra Natura saboteur, Sering, destroys her habitat and kills the crew. The primate-bearing “Barrel” burns in atmosphere, while the “Flask” of uplift virus falls intact. Kern flees in the Sentry Pod, uploads a copy of her mind, and keeps vigil. Not long after, Earth’s radio goes dark; an electronic plague collapses human infrastructure. Alone in orbit, Kern sleeps and wakes by trigger, guarding a world now seeded with unintended heirs.

On the surface, jumping spiders begin making conceptual leaps under the nanovirus. They cooperate, domesticate aphids, and expand—early signs of a culture that can select for learned “Understandings.” Generations later, named lineages such as Portia and Bianca emerge as explorers, artisans, and scholars. They face an existential threat from an ant supercolony that practices agriculture, metallurgy, and coordinated warfare. Through fieldcraft, chemical innovations, and a daring infiltration that collapses the colony’s social web, the spiders turn the ants from enemies into tools and collaborators, accelerating their ascent.

Centuries from home, the ark-ship Gilgamesh follows Old Empire star charts. Classicist Holsten Mason decodes a distress call from Kern’s system. When the ship arrives, Kern’s satellite forbids approach; her unstable persona denounces them as usurpers of her experiment. Under pressure, she bribes the humans with star maps to another site. Commander Vrie Guyen accepts, but seeds a bleak backup colony on a gas-giant moon before departing. A mutiny erupts: colonists refuse exile and hijack Holsten and Chief Engineer Isa Lain, aiming to land. Kern cripples their pursuers and, when talks fail, fires on the shuttle, which crashes. On the ground, organized ants attack; a watching spider is shot, souring first contact. Security Chief Lem Karst extracts Holsten and Lain and, at Kern’s insistence, destroys the crash site to deny technological contamination.

The refugees press on to a second terraforming station. Gilgamesh scavenges an immense Imperial archive while Lain’s teams navigate hazards from the electronic plague that spared their crude systems. Guyen secretly pursues a mind-upload facility, intent on returning to war with Kern. As spider civilization blooms, a devastating plague ravages their cities. Portia and peers discover inherited immunity and, crucially, identify the “Messenger within”: the nanovirus that writes Understandings. Combining an immune fragment with the Messenger, they create a serum that cures Bianca and, unexpectedly, allows adults to accept new Understandings. Knowledge becomes modular and tradable, society reconfigures around adult learning, and orthodoxy loosens enough to attempt replying to the orbiting “Messenger.”

Back in orbit around the grey, fungus-choked world, Guyen reveals his endgame: upload his mind to command the ship and overthrow Kern. He awakens generations of followers, turning the Gilgamesh into a shanty of laborers. At his public “ascension,” Lain executes him mid-transfer; a fragmented digital Guyen still infects systems but is contained over bitter years. The moon colony’s last messages, which Guyen hid, reveal it died; Lain’s ad‑hoc engineers keep the failing ship alive through strict population control. She and Holsten share a fragile bond across centuries; she shows him a frozen embryo—their daughter—to be awakened if a world can be won.

Meanwhile, the spiders push skyward. They teach the Messenger to “see” images by encoding pictures in radio, and Kern—at last—faces the truth: her “monkeys” never took root; the spiders are her unintended heirs. She resolves to help them. In a daring balloon-and-capsule ascent, Portia performs a near-vacuum EVA to free their first satellite; her small male second, Fabian, sacrifices himself so she can live. With orbital footholds established, Kern apologizes and shares origins and purpose in plain words.

Years pass. The Gilgamesh, failing and out of time, returns to Kern’s world. Holsten receives planet-bounced warnings to leave, but Karst and Doctor Renas Vitas adopt a prisoner’s dilemma logic: better to strike first. Lain authorizes drones that burn through the ancient Sentry Pod, sending Kern’s shell planetward—yet Kern survives, downloaded into an ant supercolony tended by a spider scientist also called Fabian. The spiders, unified by Kern’s clear warning about humanity’s record, have raised an equatorial orbital web and the Great Star Nest. Bianca rides a space elevator to command; Portia leads armored astronaut-soldiers across silk-latticed habitats.

Gilgamesh’s lasers rake the web; rocks and drones exchange fire. Portia’s teams clamp to the ark-ship’s hull, guided by Bianca and a chastened Kern. Humans jam and counterattack; Karst’s EVA squad is lured into webs and destroyed. Inside, Portia’s squads breach with acid and deploy a ventilation-borne neuroagent derived from ancestral studies of a long-imprisoned human. As hallucinations and paralysis spread, Vitas shuts life support to compartmentalize, then is overrun in her lab. Alarms die; comms fail. Lain and Holsten make a last stand as spiders cut through—Holsten chooses to hold Lain rather than swing a weapon when the breach opens.

The spiders choose conquest’s opposite. Having learned from the ant war, they isolate a minimal, inheritable nanovirus variant keyed to mammalian empathy—designed not to coerce thought but to recode recognition so humans and spiders perceive one another as kin. A shuttle lands at Seven Trees before the world’s eyes: infected humans step into a sea of arachnids without fear. Portia witnesses an elderly human—the oldest among them—laid gently on the grass beneath a shared sky, a symbol of a different future.

In the aftermath, an integrated civilization emerges. Human engineering, spider biotech, and Kern-derived intelligences blend into living starships. Decoding a structured signal from a known terraforming site, a joint crew launches Voyager. Portia commands; a Kern-offshoot minds the ship; among the human crew is Helena Holsten Lain, heir to two lineages. As Voyager leaves the webbed world, humans and spiders resume the long journey together, carrying their history—and their hard-won empathy—back to the stars.