A short recap of each published chapter, in order. These give away what happens — read only as far as you have.
Narrated by Eira Carrera. While Eira works her shift at a failing museum, her house burns down — the curling iron she left on, blamed — and a landlord's voicemail delivers the news. At the cliffs where she goes to think, she meets a sharply dressed stranger who already knows her name and calls himself an archivist. When she demands proof of his stranger's claims, he tells her to close the car door. She does, and the car climbs into the sky.
Narrated by Hugo Tria — the stranger, named here. The same evening from his side: he had watched the fire and judged Eira's odds of suicide at fifty-fifty, but didn't cause it. Aboard his ship (a craft that only looks like a car) high above Caligo, Eira refuses to go home and asks to cross the galaxy; the ship can't. Hugo reaches his partner, Vesper, decides to treat Eira as "triage" rather than a friend, and they set out for the garden town of Oxbow.
Narrated by Vesper Dio. Vesper mourns a matchmaking scheme that has just collapsed, then answers Hugo's call for help. She translocates to Oxbow, meeting him in person, while Eira sleeps off eleven exhausted hours. Watching Hugo wait through the night for Eira to rest — and the way he looks at her — Vesper privately decides there's an "inferno" forming under his denials. She comforts Eira, joins her hand to Hugo's, and moves all three off the planet.
Narrated by Eira Carrera. They arrive on Coda, but at the edge of its twilight band rather than a city, to dodge the Consortium's surveillance. The heavy gravity and thin air nearly kill Eira; Hugo threads part of himself through her body to keep her going until they reach town. At an overwhelmed alien medical facility she's offered wholesale replacement of her "insufficient" body — even a full upload into the Consortium. She refuses, and counters with a request for "an exoskeleton mech suit kind of thing."
Narrated by Hugo Tria. Eira's "option" becomes a matte-black nanocarbon suit. As they shop Coda on a logged trial account, Hugo — his mind split across many tasks at once — monitors her vitals, files paperwork for Caligo's quiet induction into the Quorum, and scouts her a home near the industrialist Nellie Platin. Eira adapts quickly, even eating a dessert that would be lethal without her new safeguards. But she tells him plainly that relocation hasn't fixed her: she wants to stay herself, keeping the option to die. In answer, Hugo offers her access to his database through her visor — a way to make integration feel thrilling — and she takes it.
Narrated by Vesper Dio. Nearly a "turn" after Coda, Vesper is back on Vellum consoling her old coworker Cariad, then pops to Eira's new Coda house — where Hugo waits on the back porch while Eira, bored of Coda, reluctantly networks with her arrogant neighbor Nellie Platin. Eira agreed to it only on the condition that Hugo take her somewhere new, so Vesper lobbies for Threnos, a silica planet at the galaxy's edge (really so she can pair Eira with her friend Clara and keep the group together). Woven through it is Vesper's memory of the closest Hugo ever came to friendship — a young revolutionary he fought beside as "second-in-command," then walked away from when the cause was lost. Eira, reading Hugo's dismissive notes on Threnos off her visor, decides that settles it: they're going.
Narrated by Hugo Tria. The group reaches Threnos — a molten-cored glass sphere Hugo can't stand, ringing with the constant "song" of its native Threnic, crystalline shards that rise from the sea to mimic your shape. One greets them as "Nodes Tria and Dio"; Eira, delighted, nicknames it "Melody" and insists they attend its funeral rite, the Sonorium. On the way she finally asks what "the Array" is — and Hugo tells her: it's what he, Vesper, Clara, and a handful of others are, "machines running some manner of self," designed by "something long-gone and forgotten." At the rite — spires tuned to call the dead home — Hugo seethes at the galaxy's delusion of "containing the dead," while Eira, for once, simply watches, present in a way his data-flooded mind can't be.