Fassin is sent back into the Dweller depths on a mission: find a list, supposedly hidden somewhere in the Dwellers' vast and chaotic archive of their own history, that contains a secret about wormhole locations. The Autumn House, his family's estate, is the last place of ordinary life before everything changes.
Source: The Algerbraist
Chapter 2: Destructive Recall
The destructive recall: Fassin's immersion in Dweller society, his relationship with Valseir the ancient Dweller who may know where the list is, and the increasingly aggressive external pressure from the approaching fleet of the Archimandrite Luseferous.
Source: The Algerbraist
Chapter 3: Nowhere Left to Fall
Nowhere left to fall: the siege of Fassin's home system tightens. The Dwellers remain indifferent, Fassin digs deeper into the archive, and the gap between the urgency felt by every other species and the Dwellers' geological-timescale unconcern is the novel's central comic and philosophical tension.
Source: The Algerbraist
Chapter 4: Events During Wartime
Events during wartime: the battle for the system begins in earnest while Fassin moves through Dweller politics, which operate on timescales that make war seem like weather. The list's significance and the truth about what it actually contains begin to emerge.
Source: The Algerbraist
Chapter 5: Conditions of Passage
Conditions of passage: Fassin has found what he came for and the problem of getting it out, and getting it to anyone who can use it, and surviving long enough for any of this to matter, is the final act's central problem.
Source: The Algerbraist
Chapter 6: The Last Transform
The last transform: the revelation about what the list actually is and what the Dwellers have actually been doing for several billion years. Banks's disclosure is structured to reward both readers who guessed and readers who did not, and the irony of it is delivered straight.
Source: The Algerbraist
Epilogue
An epilogue: the system's fate, Fassin's fate, and the Dwellers' continued indifference to all of it. The novel closes on the longest possible view of events, which makes the human urgency of everything that preceded it feel exactly as small as the Dwellers always said it was.