A distant prequel to Vinge’s 1992 masterpiece, A Fire Upon the Deep, with a single character in common. Some 8,000 years hence, the Qeng Ho interstellar trading fleet investigates the enigmatic OnOff—a star that shines for 35 years, then extinguishes for 250; once understood, its weird physics may yield an improved star drive. Meantime, its single planet harbors intelligent aliens, the Spiders, divided into warring factions, but thought to be descendants of an advanced starfaring civilization. During the Dark, they survive frozen solid in pools of ice. Also arriving at OnOff are the acquisitive, ambitious Emergents. Cooperating at first, the Emergents later mount a treacherous sneak attack, defeating the traders and enslaving the survivors. The Emergents’ overwhelming advantage is Focus, the result of a brain-infecting virus that can be induced to secrete mind-controlling chemicals. Those Focused are instilled with unswerving loyalty. The Emergents are led by a smiling deceiver, Tomas Nau, his sadistic assistant, Ritser Brughel, and personnel genius Anne Reynolt, once Nau’s greatest adversary, now enslaved and Focused. The Qeng Ho resistance is thin, consisting of legendary genius and onetime leader Pham Nuwen, whose failed dream of a Qeng Ho galactic empire forced him into exile; young trader Ezh Vinh; and, secretly, Ezh’s love, linguist Trixia Bonsol, now Focused and translating the Spiders’ language. Both the Emergent and Qeng Ho fleets lost interstellar capability during the battle, so the humans must wait until the Spiders develop technology advanced enough to help them. As the OnOff star reignites, the Spiders emerge from their “deepnesses” and, galvanized by genius Sherkaner Underhill, burst into a frenzy of technological development. Nau plans to trick the Spiders into destroying themselves in a nuclear war. Pham, meanwhile, schemes to defeat Nau but sees in Focus the key to realizing his old dreams of empire. Huge, intricate, and ingenious, with superbly realized aliens: a chilling, spellbinding dramatization of the horrors of slavery and mind control.