The Dog Star, Sirius, is falsely convicted of murder and sentenced to one mortal lifetime in the body of a dog on planet Earth. If he can recover the mysterious Zoi his sentence will be lifted and he will be allowed to return to the heavens to his former role as Denizen of Sirius. He is born into a litter of puppies to part-Labrador Bess, belonging to cruel Mrs. Patridge and Mrs. Canning.
After surviving being thrown into the river in a sack, Sirius is rescued by Kathleen O'Brien, an Irish girl who is living with her distant uncle, Mr. Duffield, and lazy, prejudiced aunt, Daphne "Duffie" Duffield, and their two sons Basil and Robin. After bargaining with Duffie to allow her to keep Sirius in exchange for handling all future house chores, Kathleen takes Sirius home.
As he grows, Sirius fights with external conflicts as well as internal complications, when his past as a luminary clashes with his current life as a dog. Sirius makes friends with the Duffields' three cats: Tibbles, Remus, and Romulus. Through his search for the Zoi, he also meets the town's many occupants: Miss Smith, Mr. Gumble, the policeman, and his siblings Bruce, Patchie, Rover, and Redears.
In his desperate search for the Zoi, Sirius receives help from not only his friends but also Sol (the sun), Earth, and Moon, all the while he fights to find a balance between his dog-self and his star-self. Sirius embarks on an adventure that showed him humor in desperation, cruelty in kindness, and hope in hopelessness.
Yet even with a dog hero, Jones does not overload us with cute animals. Instead they are dangerous and, by and large, rather stupid. Of course, so are the humans, so the struggle between human and animal isn't entirely one-sided. Dogsbody has become, deservedly, a classic, not despite but because of its completely nontraditional cosmology.