A Fire Upon the Deep

A Fire Upon the Deep is a science fiction novel by the American writer Vernor Vinge, published in 1992. The book is a space opera with variable physics, space battles, aliens and superhuman intelligences, plus a messaging system much like Usenet, and the 1993 Hugo for Best Novel was shared with Connie Willis's Doomsday Book. A Deepness in the Sky, a loose prequel, dates from 1999, and The Children of the Sky, its direct sequel, followed in 2012.

The galaxy is layered. Near the middle, intelligence stops working; further out, civilisations are ordinary; at the rim, minds become something else again. An expedition from Straumli Realm investigates a newly discovered data archive, and the researchers accidentally wake a superintelligence that comes to be known as the Blight, which gradually compromises their facility, and the novel begins in the middle of that failure rather than before it.

The humans who wake it end up fleeing with it in a ship that goes further than they intended, with two children aboard, and the chase pulls in a trader crew that is not equipped for a rescue of this size. It also involves an ancient power and a world where dogs are not one mind each but packs of minds that have to agree before they can think.

Vinge builds the novel out of two plots that converge, a family stranded on an unfamiliar planet and a rescue attempt organised by people who do not know what they are dealing with. It is a standalone story within a setting that later books explore, and the 1993 CD-ROM edition included annotations by the author about his intentions in different parts of the book.