Twenty days after fleeing the High Lab, Johanna Olsndot is awake for the landing. She and her brother, Jefri, are the only children not in coldsleep; there are over 300 children in suspended animation. The cargo shell’s interior is dangerously hot, and many coldsleep boxes are failing. In the main cabin, their parents—Arne and Sjana Olsndot—prepare for a risky planetary landing. Their ship has no wings, atmospheric shielding, or antigravity generator, only a single rocket torch. They descend toward a habitable world that shows signs of pre-technological civilization (roads, towns, and castle-like structures) but has no aircraft or radio emissions.

During the descent, Johanna notices a gray, moldlike discoloration spreading across part of the hull and recalls overhearing her parents say that they created a dangerous entity at the Lab but that they also now carry a countermeasure to oppose it. The family selects a landing site in the thinly populated hills of the planet’s mossy, mountainous arctic region. Despite the risk of causing a steam explosion and fire, they land successfully.

Peregrine Wickwrackrum, a pilgrim, travels with his two companions toward Flenser’s Castle on Hidden Island. Scriber Jaqueramaphan is a talkative fellow whom Peregrine suspects of being a spy; Tyrathect is a reserved newcomer whom he believes to be a Flenserist fanatic. Peregrin and his companions belong to a dog-like species; each individual consciousness, or “soul,” is a hive-mind “pack” comprised of multiple members whose individual traits and memories contribute to a deeper personality that is more than the sum of its parts. Peregrine is a pack of four, Jaqueramaphan a pack of six, and the conflicted Tyrathect a newer, less cohesive pack of five.

As they descend through coastal valleys, the travelers hear a deep rumbling and see a brilliant light descending from the sky—the Olsndots’ cargo vessel. It lands with tremendous heat and noise several miles away. Peregrine privately confirms that Scriber is a spy when the latter uses an optical device to observe the site and spots camouflaged Flenserist troops moving into ambush positions. He warns that Tyrathect is likely a high-ranking Flenser operative. Despite the danger, Peregrine is fascinated by this visitation from beyond his world, and the two settle in to watch events unfold.

Five hours after landing, Arne and Johanna exit the ship and move a number of coldsleep boxes outside for better cooling while Sjana stands guard. Without warning, the Flenserist ambush begins. An arrow strikes Johanna in the chest. The attacking packs of dog-like creatures use choregraphed movements to wield bows, axes, and blades. Arne returns the attack, using his pistol with devastating effect as his pressure suit protects him from arrows. However, when he runs to rescue Johanna, a creature intercepts him and tears open his throat. A pack armed with primitive flamethrowers then rushes forward and sprays burning liquid across the landing site, engulfing Sjana’s position and the rows of coldsleep boxes. A horrified Johanna sees the plastic containers melting just before she loses consciousness.

Peregrine and Scriber watch the ambush from hiding. After the flames die down, they see that one alien (Johanna) has been carried away alive. Against all prudence, Scriber proposes that they rescue her. Descending toward the landing site and crossing through the mob of wounded Flenserist soldiers, Peregrine and Scriber run the risk of blending their consciousnesses with the surviving pack-fragments and losing their mental stability and identities. When Peregrine takes clothing from fallen members, intending to clothe his own members in a Flenserist disguise, he is attacked by a grieving fragment, and one of his own members, Rum, is fatally slashed. As Rum dies, Peregrine’s composite consciousness disintegrates, and his remaining members start to revert to individual, nonsentient animals. Suddenly, a scarred singleton begs to merge with his remaining three members, and in desperation, what is left of Peregrine melds with the singleton, forming a new four-member pack: Peregrine Wickwrackscar. The new member, formerly of the Flenserist fanatics, brings Peregrine new military knowledge and experience. Scriber Jaqueramaphan looks on in horror, but when he confirms that Peregrine is “Peregrine still, but Wickwrackrum no more” (43), Peregrine states that as a pilgrim, he is familiar with the process of losing and gaining members; his “soul” is flexible enough to withstand the strain but remain cohesive.

Now disguised in Flenserist uniforms and using Scar’s knowledge of the Flenserists’ passwords, Peregrin and Scriber follow the “white jackets” pack transporting Johanna; they kill him and take possession of the unconscious alien. At the harbor, they see Tyrathect appear; she is wearing Flenser’s colors and initiates an Incalling—a mental summons that draws all nearby Flenserist packs toward the fortress. Scriber and Peregrine are horrified to realize that they have been unknowingly traveling with a surviving fragment of the ruthless Flenser, leader of the movement that bears his name. Taking advantage of the unexpected diversion of Tyrathect’s Incallling, Peregrine and Scriber scuttle the front boats at the harbor and escape in a fast reconnaissance vessel with Johanna aboard.

Having been overcome by smoke during the packs’ sudden attack, Jefri Olsndot regains consciousness to find himself a prisoner; he is transported to Flenser’s Castle on Hidden Island. Due to a servant’s miscalculation, he is placed in the wrong room—an old-fashioned schoolroom with primitive writing materials. Exploring the area, Jefri discovers that he shares the space with a pack of puppies. The young creatures are friendly and playful, and one mimics his voice precisely. Jefri convinces himself that his parents are safe elsewhere in the castle, negotiating with their captors.

The narrative shifts to Lord Steel, the current ruler of Flenser’s domain. The pack that is Lord Steel is a particularly sadistic personality that Flenser created by ruthlessly culling specific pack members and adding others to create the precise configuration of traits that he desired to cultivate. Now, Steel meets with Tyrathect, who claims to be the surviving remnants of Flenser himself, returning in the aftermath of an assassination attempt that was thought to have succeeded. Steel recognizes his creator’s distinctive voice and mannerisms in Tyrathect’s bearing and confirms that Tyrathect includes at least fragments of the original Flenser. Tyrathect explains that Flenser survived assassination by dispersing his consciousness among loyal follower packs who then escaped the massacre. Currently incomplete, he agrees to take a subordinate role as Flenser-in-Waiting, until the other fragments make their way back to Hidden Island to complete his reconstruction.

Ravna Bergsndot, a citizen of the human-populated planet, Sjandra Kei, reflects on her daring decision to move away from her home and take her current position as a librarian at Relay, a major communications hub that lies 20,000 light-years away from Sjandra Kei. Grondr Vrinimikalir, a high-ranking member of the Vrinimi Organization, which runs Relay, summons her to a meeting and explains that the Straumli disaster—the creation of a malevolent superintelligence called a Class Two Perversion—has made Ravna valuable as Relay’s only human employee. A different superintelligence, or “Power” from the Transcend, known as Old One, has arrived in the Beyond, seeking information about the Straumli Perversion. It has offered extraordinary compensation in exchange for acquiring a living human to study, and Grondr inquires as to whether Ravna would be interested in going with Old One.

Ravna angrily refuses to be sold, and Grondr reassures her that they would never “abuse” her by going against her wishes. Gronder then reveals that Vrinimi Org has another candidate in mind: a human that has been recovered from a derelict ship and essentially brought back to life; the human had been found at the bottom of the Slow Zone or “Slowness,” a region below the Beyond, where faster-than-light travel is impossible and even simple automation fails. Vrinimi researchers have revived the sole surviving crew member, who represents a genetic branch of humanity that was lost long before the dawn of modern civilization in the Beyond. Grondr asks Ravna to help orient this human to his new reality.

Ravna meets the revived human, Pham Nuwen, on the Relay Docks and is amazed to realize that he has managed to learn the Triskweline trade language in 30 days. He explains that he is the one who insisted on meeting Ravna so that he might gain a more honest perspective on his situation. Pham recounts his history; he was born a prince on Canberra, a medieval human colony in the Slow Zone. At age 13, he was taken by the Qeng Ho, an interstellar trading fleet, and worked his way into their organization. Over a subjective lifetime of 67 years (that nonetheless spanned millennia due to the issues of long-distance space travel and relativity), he became a successful shipmaster of the Qeng Ho.

Pham’s final voyage—an ill-fated expedition toward the galactic core—ended in disaster when his fleet penetrated too deep. The organizer of the expedition had reasoned that higher-evolved civilizations would be located nearer to the core, not realizing that the opposite is true. As the team approached the Unthinking Depths, their technology waned in tandem with their own intelligence, and they never realized that the specific region of space was responsible for their doom. Eventually, everyone died.

Now, however, the rejuvenated Pham is enthusiastic about the Vrinimi Organization’s plan to send him to Old One in the Transcend; he merely views this prospect as another adventure and relishes the idea of hopping to an even more advanced plane of existence than the Beyond, which is already far beyond his previous life in the Slowness. Ravna, realizing that the Transcend might hold unknown dangers for Pham, tries to dissuade him, but her efforts fail.

Grondr later tells Ravna of the larger crisis behind the current situation. Old One has been monopolizing Relay’s communication bandwidth for 20 days, with usage peaking at nearly 5% of capacity; this level of usage by one client is threatening the Organization’s relationships with thousands of other customers. However, the Organization is at a loss as to how to set boundaries with a Power, a superior technological intelligence. Understanding the stakes, Ravna resolves to change Pham’s mind about going to the Transcend with Old One.

Ravna takes Pham on a tour of the Foreign Quarter on the Relay Docks, ending at a bar that caters to traders from across the Beyond. They meet Blueshell and Greenstalk, two Skroderiders—ancient plant-like beings who use wheeled platforms for mobility and memory. The two traders initiate the conversation, and Ravna is delighted to realize that they speak her native language, Samnorsk. The Skroderiders captain a small freighter whose cargo was rendered worthless after they stopped at Straumli Realm, which had just been contaminated by the malevolent Class Two Perversion mere hours ago. Amazed to be hearing the next-best thing to a firsthand account of the disaster, Ravna presses for more details. The discussion turns to speculation as to how the Straumers were deceived by the entity, with Blueshell and Ravna explaining that advanced malicious programs in the Transcend can manipulate their creators by corrupting data streams.

Blueshell then reveals the critical information that some High Lab researchers suspected the birth of a Perversion and planned to escape with the “recipe” for a countermeasure before they and all of their assets could be fully incorporated into the Power’s design. The researchers planned to rendezvous at the Bottom of the Beyond—right on the edge of the Slowness—where they would signal Relay via a long-distance communications technology known as an ultrawave. The Skroderiders admit to having engineered their meeting with Ravna, hoping that she, as a Vrinimi employee, could connect them with people who would take this news seriously enough to send help to the stranded researchers and retrieve the countermeasure.

Later, Ravna invites Pham back to her apartment and shows him the unamplified view of the Milky Way galaxy. Having heard the Skroderiders’ explanations about the Straumli Perversion, he admits that he better understands the dangers of the Transcend. He and Ravna make love and spend the night together.

A message posted on the Net (the online network spanning thousands of civilizations across the galaxy) reveals that Old One’s emergency bandwidth demand has consumed over 60% of Relay’s capacity, threatening to drive its customers to other competitors.