It follows the lives of Tod, a red fox raised by a human for the first year of his life, and Copper, a half-bloodhound dog owned by a local hunter, referred to as the Master.

Heavily modified from the source material, Disney's The Fox and the Hound was released to theaters in July 1981 and became a financial success.

Tod is a red fox kit, raised as a pet by one of the human hunters who killed his mother and litter mates.

As Chief skillfully trails the fox, Tod flees along a railroad track while a train is approaching, waiting to jump to safety until the last minute.

With Chief buried and Master crying over a dead dog he trains Copper to ignore all foxes except for Tod.

That winter, the Master sets out leg hold traps, which Tod carefully learns how to spring, but the vixen is caught and killed.

The Master spends most of his time drinking alcohol, and people begin trying to convince him to move into a nursing home, where no dogs are allowed.

[1][2] He stated that they were "so tame [that he] could turn them loose and watch them hunt, fight, make love, and live an almost normal life.

For example, he notes that while people have told him that foxes do not really run among sheep or cattle herds to escape hounds, he himself used to watch them do just that from his bedroom window.

[1][2] Mannix felt it was nearly impossible for any writer to escape imparting some anthropomorphism in such a novel, as a human must guess at the way an animal's mind may work and what motivations it may have.

[1][2] The last chapter of the novel, covering Copper's last hunt of Tod, was based on the story of Boston, a fourteen-month-old bloodhound–foxhound mix, and Old Baldy, a red fox known by hunters for having outrun numerous packs of hounds put on his trail.

[3] Mannix originally read the story in a Recreation magazine article, which stated that in December 1887, near the James River in Virginia, Boston hunted a fox referred to as Baldy for a day and a half, covering 50 miles (80 km) of terrain.

[13] Reviewing the novel for Best Sellers magazine, William B. Hill considered it a "corking good novel", praising it for its "simplicity and straightforwardness" with the dog and fox being "real" rather than allegories for social issues.

[14] Robert Ramsey of the Placerville, California, Mountain Democrat thought the book worthy of winning the Dutton award, characterizing the narrative as "always interesting" and principal characters Tod and Copper as "unforgettable", while praising Mannix's "ability to enter into the world of animals and portray it".

[2] A reviewer for the Catholic Library World considered it a "memorable and delightful reading experience" written by a man "who knows the ways of foxes".

[15] Author and sportsman Richard Alden Knight praised the novel, stating that it "surpasses any writing I have ever encountered on the thinking processes of animals"[16] and that the story of a duel between natural enemies is "told well and written with feeling".

[17] A reviewer for the Reading Eagle felt Mannix wrote well enough to make a reader feel like they were the characters Tod and Copper and that the story was "really exciting" due to the "dramatic opposition" of the two animals.

Reitherman had his own ideas on the designs and layouts that should be used; however, the newer team backed Stevens, except Don Bluth, who felt Disney's work was stale.

By the time it was completed in 1981, the film had changed into a chronicle of the unlikely friendship of two creatures, who should be natural enemies and who learn society sometimes tries to determine their roles despite their better impulses.