Deep deep deep in the thickest part of the thicket, far beyond malls and subdivisions, Quickly Marts and Fotomats, live the gnomes. They grow to heights of six inches, weigh about 10 ounces each, are seven times stronger than humans and have life spans of 400 years.

Also, they are hot properties. A costly but whimsical book, "Gnomes," became a stocking-stuffer best seller in both hardcover and paperback editions. The merchandising will continue with a Broadway show and record albums and, tonight, "Gnomes," a pretty darn charming one-hour animated CBS special, at 8 on Channel 9.

Obviously the Gnomes hope to follow the Hobbits and the a Peanuts into a similarly lucrative cranny in popular consiciousness. Worse things could happen. These little beasties, according to tonight's special, have a society highly similar to that of humans, but they differ dramatically in that they mean no one any harm.

That does not mean no one means them any harm. "Life is never quite perfect," says the sonorous, dignified narrator, Lee Richardson. And so the gnomes must live in fear of the trolls, a miserable ring of louts who have no more table manners than the average network executive. While the gnomes are "always ready for a lark or a tease" and are "above all, good-natured," the trolls are a destructive menace with whom peaceful coexistence is not possible.

Hence we have the perfect allegorieal fantasy for the new age of brinksmanship Ronald Reagan is about to usher in.

In the story, by Sam Moore and Maurice Rapt, a 101-year-old gnome named Tor is about to be married, but the trolls intervene out of pure contrary maliciousness. Uncle Kostja, a Siberian gnome, arrives from -- where else? -- Siberia only to be nearly buried under a pile of troll-thrown rocks. "Oops!" he says. "I came a thousand miles for this?"

Worse comes inevitably to worst when the trolls threaten the ecomaniacal gnomes with the doomsday weapon, a forest fire. Tor and a beaver undertake to save the day.

Visually, the program is a welcome relief from those increasingly uninteresting "You're in Your 17th Rerun, Charlie Brown" specials. The only time director Jack Zander allows the program's warm, distinctive style of drawing and autumnal color scheme to be violated is for a brief interlude of banal mush built around an inoffensive love song. Among the able voices in the cast is the unfailingly recognizable Joe Silver, whose wellbottom baritone helps make one of the trolls an engaging degenerate.

"Gnomes" as a commercial glut may not be a terribly welcome prospect -- especially with those good-for-nothing Kiliban cats having apparently exhausted their ninth life at long last. Now there were cats; big deal. But then anything as a commercial glut is not a terribly welcome prospect. America's imaginary menagerie has to be filled with something, and these spry goody two-shoeses are better than a lot of dumb smirking felines.

Tonight's special may signal an outbreak of gnomonia that it would be pointless folly to decry.