Dogsbody has as its point of departure dissension among the Heavenly Bodies, during which the Dog Star, falsely accused of murder and the loss of a Zoi [a symbol and agent of power], is condemned to be born on earth as a pup so that he may search for the sacred object, which has fallen as a meteorite…. [The pup, Sirius,] is rescued by Kathleen, a waif from Ireland taken in unwillingly by stony-hearted Mrs. Duffield who sees in this relative of her husband's a useful domestic slave. Child and dog endure blows and insults, and Sirius suffers a persecution from the heavens which he only understands after he has remembered, piece-meal, his own origin. Like all Diana Wynne Jones's fantasies, this is a confident, intricate interweaving of contemporary family tensions and alliances with flashes of extra-human activity, as stars and planets join in the search for the Zoi and make their several contributions to the final unravelling of plot and counter-plot. The parallel between Duffie's cruelty to Kathleen and the ruthless actions of Sirius's Companion is significant. The conflict is not a moral so much as a psychological one, and the fantasy, with its constant emphasis on light and darkness, is there to make a point about human behaviour. (pp. 2771-72)
Margery Fisher, "Darkness Against Light," in her Growing Point, Vol. 14, No. 6, December, 1975, pp. 2769-73.