Cytonic

Cytonic, the third book in the Skyward series, continues the story of Spensa Nightshade, a young fighter pilot from Detritus, a human colony encased in orbital debris. In the previous books, Spensa discovered her cytonic abilities: rare psychic powers enabling teleportation and mind-to-mind communication. She also learned that the Superiority, the galactic government imprisoning her people, is controlled by Winzik, who seeks to weaponize the delvers, entities from another dimension capable of destroying planets.

Trapped on Starsight, the Superiority's space station, Spensa activates a portal into the nowhere, the dimension cytonics pass through during teleportation. She carries M-Bot, her AI companion in a small drone, and Doomslug, a hyperspace slug. In the void, she senses the delver she once persuaded not to destroy Starsight. It pleads for help and directs her toward the Path of Elders, a sequence of ancient portals containing early cytonic knowledge. The other delvers, identical beings that despise change, react with hatred upon recognizing Spensa. Rather than return home, she pushes Doomslug toward Detritus and throws herself into the unknown.

She emerges onto a floating jungle fragment in the belt, a boundary region where matter from ordinary reality has leaked into the nowhere, forming drifting landmasses. M-Bot tumbles out beside her, but Doomslug is gone. Pirates capture Spensa and confiscate her father's pilot's pin, identifying it as a reality icon: an object that generates reality ashes, silvery dust that prevents memory loss. Spensa senses a warm, fatherly presence from the pin but cannot explain it.

A mustachioed human named Chet Starfinder rescues Spensa, riding a dinosaur-like creature into the pirate camp. As they flee, they witness a delver-possessed pirate, eyes glowing white, screaming at Spensa. Chet explains the belt: Hundreds of fragments orbit the lightburst, a light sphere where the delvers reside. Without reality ashes, anyone here gradually loses their identity. Chet has been here 170 years and remembers almost nothing. M-Bot's databases reveal Chet's arrival matches when M-Bot's ship crashed on Detritus. Chet produces a uniform patch reading "SPEARS," M-Bot's lost pilot, but insists he would never have kept an AI.

That night, Spensa's sleeping mind reaches Jorgen, her flightleader and romantic interest, who reveals he is also cytonic. The Superiority is mobilizing for war. She also overhears Winzik's operative Brade offering the delvers a deal: Winzik will round up every cytonic if they serve him.

At the first portal on the Path, Spensa activates a vision of the nowhere's ancient past, watching matter leak through dimensional weak points to form the first fragments over centuries. The revelation is transformative: Cytonic powers are mutations caused by the nowhere's energy seeping into ordinary reality. Cytonics predate the delvers entirely. Spensa is elated; she is a natural mutation, not a monster. The delvers retaliate by ramming a dense fragment into hers, destroying the portal.

Spensa and Chet infiltrate the Broadsider pirate base to steal a ship, but Spensa is captured by Captain Peg. Over two weeks, she works with the crew and learns all belt weapons are nonlethal. When Peg recognizes Spensa as a soldier, Spensa and M-Bot commandeer a ship, but ascending too far from the fragments causes memories to fade. Peg offers a deal: Defeat the pirate champion for a ship and passage to the next portal. Peg's larger aim is to unite the factions and recapture Surehold, the Superiority base where her children are held.

At the second portal, a vision shows ancient humans establishing contact with the UrDail, an alien species, before either group had space travel. A cytonic woman communicates across time, warning that a "beast" created by an advanced species destroyed nearly all gathered cytonics. She directs Spensa to find the memories of Jason Write, the human who triggered humankind's galactic expansion.

At the championship, Spensa discovers the reigning champion is Hesho, a kitsen (a small fox-like alien) and the emperor she thought died at Starsight. He retains his warrior instincts but remembers nothing of his former life. Spensa defeats him. Peg reveals her estrangement from her sons was staged and that the pirate raids were covert military training. Her victory unifies five of six factions. Meanwhile, Winzik convinces the delvers that cytonics are multiplying, and the delvers formally accept his deal. When a delver-sent fragment nearly destroys the base, Spensa insists the assault on Surehold happen the next day.

During the battle, the delvers warp buildings from a Superiority city into the belt. Spensa engages Hesho, who is possessed mid-fight, his eyes glowing white. She confronts the delver, but the delvers try to erase her identity. She is saved by Doomslug, disguised all along as the reality icon through shape-shifting, and by Chet, who feeds Spensa her memories. The delvers offer a truce: If Spensa stops following the Path, they will leave her people alone. She neither accepts nor rejects. After Surehold surrenders, Spensa recruits Hesho, who declares himself her sworn companion.

Spensa faces an agonizing choice. Chet asks her to explore the nowhere; Peg offers a permanent home. Reaching out to the fatherly presence in the icon, she receives not guilt but warm permission to stay. The permission paradoxically gives her the courage to leave: She cannot trust the delvers or abandon her friends.

At the third portal inside Surehold, a vision shows Jason Write entering the nowhere centuries ago with a metallic sphere: an AI built from his deceased wife's voice and memories. Chet breaks down and confesses he is the delver Spensa changed at Starsight. He reconstructed Commander Spears from the delvers' collective memory, filling gaps with traits from Spensa's mind. The revelation: Delvers are descendants of AIs brought to sapience by the nowhere's energy, just as cytonics are beings changed by the same exposure.

At the Solitary Shadow, the final portal near the lightburst, Spensa witnesses the AI's crisis. After Jason's death, the grief-stricken AI, only days old emotionally, deleted its memories, locked its personality, and copied itself thousands of times, creating the delvers: identical, unchanging, terrified of what they once were. Their weakness is isolation, the very thing that broke them. The delvers detect Spensa and attack.

The delvers manifest a hundred starfighters piloted by emotionless duplicates of Chet. Chet and M-Bot sacrifice themselves: Chet releases his physical form to assault the delvers, who overwhelm him, while M-Bot draws every remaining ship and is destroyed. Doomslug hides Spensa and Hesho near the lightburst, and Spensa walks the final distance on foot.

Inside the lightburst, the delvers attack en masse. One hesitates: It carries the courage Spensa once gave Chet, which no rewriting could erase. Spensa seizes it, and their essences merge. She shares her experience of living with grief, and her willingness to change sears the static delvers, who recoil. A path opens. She steps into a cavern on Detritus.

She reaches Platform Prime, Detritus's orbital station, and finds Jorgen in an admiral's uniform. She places Doomslug and Hesho on the table, then faints. Upon waking, she tells Jorgen she has found the delvers' origin, their fears, and the key to defeating them. She carries two sets of memories, her own and Chet's, and her soul changes through the merger. M-Bot survives in the nowhere as pure cytonic light, and Spensa promises to bring him back. The war continues, but Spensa has returned with knowledge that could change everything.