The introduction places A Deepness in the Sky in the same universe as A Fire Upon the Deep, noting both books’ acclaim while stressing that Deepness is not a direct prequel. It previews the novel’s focus without major spoilers, positioning the work within 1990s space opera.

It describes the OnOff star’s 250-year bright/dim cycle and the convergence of two human factions—the Qeng Ho and the Emergents—above Arachna. Below, an alien Spider civilization survives by hibernating in underground “Deepnesses” during the long darkness, making first contact a central opportunity.

The chapter frames guiding questions about survival in an indifferent universe and what ethical strategies enable it. Sherkaner Underhill embodies curiosity and discovery among the Spider-people; Ezr Vinh, a young Qeng Ho, must rapidly acquire similar skills; the Emergents pursue control through creating “Focussed” individuals, a model of managed freedom.

To illustrate outlooks, the introduction quotes Underhill’s appeal—“Pedure, there is a deepness in the sky, and it extends forever”—and contrasts it with the fragility of civilizations facing plagues, catastrophes, and impact events. It argues that adaptation and continual change are essential, and that even within the Qeng Ho, internal tensions require Ezr Vinh to mediate under uncertainty.

The essay highlights Vinge’s computer-science background, noting data-web foundations and prescient details like location-aware devices. Finally, it links Deepness to the “Slow Zone” context from Fire and suggests that Underhill represents the book’s optimistic, scientific values, which the story will rigorously test.