“The Nut Job” is animation’s rebuke to “Atlas Shrugged.” Here we have an individualist, a practitioner of the Ayn Randian virtue of selfishness, who must learn to share with others and embrace the joys of collectivization.

And by “others,” I mean other rodents. This subtext must’ve amused director Peter Lepeniotis and his co-writer Lorne Cameron, although they pepper the movie with enough dry-roasted jokes to dispel any sense of preaching.

The egotist is Surly (voiced by gravelly Will Arnett), a purple squirrel, and his me-first behavior gets him kicked out of the park.

He and his silent rat sidekick Buddy will vie with the other park animals to raid the pantry of a nearby nut shop — which is really the front for a gangster operation, and at this point further plot description becomes superfluous.

All you need to know is that the raccoon overlord of the park (Liam Neeson) exhibits too much interest in power, that the “good” squirrel (Brendan Fraser) has an oversized image of his heroism (not really a problem, because everybody else shares it too) and that sensible Andie (Katherine Heigl) thinks Surly might be redeemable.

One problem with these park denizens: They tend to look alike. There’s a mole and some woodchucks and other such toothy creatures, which makes for less visual variety, than, say, the fauna of “Bambi.”

The movie’s practically stolen by the only headlining canine in sight, a pug brilliantly voiced by Maya Rudolph — her arrival goes a long way toward sweetening a story with an unpleasant hero.

The film is fast-moving, even if its goal of catching the manic spirit of Bugs Bunny cartoons succeeds only about half the time. Its look (in 3-D, in some theaters) is just odd enough to be nicely distracting: a world of vaguely ’50s-era cars and buildings, decorated with saturated colors and one spectacular tree on fire.

Nobody’s going to mistake “The Nut Job” for Disney, but the script is in the 10-gags-per-minute style that epitomizes current TV sitcoms, and it’s funny enough to keep an adult awake for most of its running time.

Lepeniotis expanded the film from his 2005 short, “Surly Squirrel,” and financed the feature with Canadian and South Korean money.

The latter is the only explanation for the end-credits appearance of a cartoon Psy, once again flogging his Korean novelty hit “Gangnam Style” so the other critters can join in. Until that dated reference, “The Nut Job” qualifies as a mildly pleasant surprise.

“The Nut Job” (three stars)

A joke-filled tale of a selfish squirrel (voiced by Will Arnett) who gets kicked out of the park by his fellow rodents and plots the heist of a nearby nut shop. Nobody will confuse this movie with top-row Disney, but the animation is fun and it moves along nicely.

Rated: PG for subject matter.

Showing: Alderwood 7, Everett Stadium, Galaxy Monroe, Marysville, Olympic, Stanwood, Pacific Place, Thornton Place, Woodinville, Blue Fox, Cascade Mall.