Even compared to most of the mediocre kids’ computer-animated movies that arrive in theatres every week or so and quickly migrate to ancillary media, “The Nut Job” is pretty bad. One might call the picture the brainchild of Peter Lepeniotis, who directed it and co-wrote the script with Lorne Cameron, were it not for the fact that any reference to human intellectual activity in its creation would be a stretch.

The story centers on Surly Squirrel (voiced by Will Arnett), a character Lepeniotis introduced in a short back in 2005. Surly is a selfish, obnoxious rodent with only one friend, a normally mute mouse called Buddy (Rob Tinkler). When his scheme to rob a peanut cart on the sidewalk beside Liberty Park, the Oakton refuge where he lives, results in the destruction of the tree housing the communal winter food supply for all the animals there, the pack’s leader, Raccoon (Liam Neeson), spearheads his banishment, though girl squirrel Andie (Katherine Heigl), who’s unaccountably sweet on him, protests. (Point of order here: She claims that the vote has to be unanimous, which suggests that she could block his expulsion by simply vetoing it. But she doesn’t. Why?)

In any event, Surly is sent off to make his way in Oakton, where he’s immediately accosted by some nasty rats. It’s no time, however, before he finds a shuttered nut store that he looks upon as pure paradise. Unfortunately, it’s been taken over by a gang of goofy thugs headed by King (Stephen Lang), who are tunneling into the bank vault next door. King’s pug Precious (Maya Rudolph) takes an instant dislike to the abrasive squirrel, setting up a series of confrontations that also include Andie, who shows up with Grayson (Brendan Fraser), the preening but dense squirrel the park denizens consider their champion; eventually Raccoon, who isn’t the benign figure he seems, makes his way to the shop as well, accompanied by a bunch of other critters. Ultimately things wind up in a supposedly exciting car chase and a face-off that’s waterlogged in more ways than one.

Of course, there’s a moral to all the shenanigans as Surly winds up learning to care about others and not just himself. But children probably won’t learn that lesson after snoozing through most of the tedious business that precedes his turnabout. It’s a major obstacle to connecting with the movie that, especially as voiced by Arnett, Surly is a distinctly unpleasant fellow who doesn’t possess the sort of giddily roguish charm that might make him brashly likable—think of Daffy Duck, for example. And as if that weren’t enough, Fraser’s Grayson is equally irritating. The rest of the characters are just ordinary, with Heigl’s Andie especially bland. In fact, only Rudolph’s Precious is likely to come across as engaging to anybody, and she’s a minor presence.

The story doesn’t make up for the misguided characterizations. Lepeniotis and co-writer Cameron manage to insert plenty of action sequences into the mix, but though they’re not badly choreographed—indeed, the animation by and large is pretty good—they grow wearisome. A proliferation of gags about flatulence and worse is inserted in order to rouse youngsters’ interest, but even that tired tactic fails. The worst thing one can say about a picture of this sort is that it’s flat and boring, but “The Nut Job” is.

And to top it off, presumably as a nod to the movie’s Korean origin, an animated version of pop star Psy shows up to lead a dance over the final credits. It’s only the last miscalculation in the story of Surly Squirrel, who garners fewer laughs over the course of 86 minutes than Scrat, the rodent from “Ice Age,” gets in three or four.