One might think that after “Paul Blart: Mall Cop” and “The Dilemma,” Kevin James couldn’t sink much lower. But you’d be wrong. “Zookeeper” is a dismal family comedy that even the most charitable child should find difficult to endure.

The obvious inspiration here is the “Night at the Museum” flicks with a change of star and venue. So instead of Ben Stiller we get James as Griffin Keyes, the nice-guy keeper at an urban zoo who’s been depressed for five years about having been dumped by blonde bombshell Stephanie (Leslie Bibb) at the very moment he was proposing to her, complete with fireworks and mariachi band. When she shows up at a pre-wedding celebration he’s hosting at the zoo for his brother, Griffin’s smitten all over again. But since he’s tongue-tied and even more klutzy than usual around her, his pals the animals break their vow not to talk in the presence of humans in order to advise him in the art of courtship.

So there’s lots of humorless babbling by such unseen luminaries as Nick Nolte (the gorilla), Sylvester Stallone (the lion), Cher (the lioness), Jon Favreau and Faizin Love (the bears), Maya Rudolph (the giraffe), Don Rickles (the frog), Judd Apatow (the elephant) and Adam Sandler (the monkey). Apart from Nolte, who gets the most soundtrack time as the ape Griffin especially befriends (even taking him out for a night on the town), their contributions are pretty limp, with Sandler, using one of those screechy voices one had hoped he’d finally outgrown, especially aggravating.

But the movie belongs to James, though if he had any sense he’d disown it—hard to do since he’s also credited as one of the producers and one of the writers. For most of the running-time he’s the genial fat guy who runs into things and falls down a lot, the same shtick that served him so well in “Blart.” But late in the day he transforms himself in order to meet Stephanie’s expectations, leaving the zoo to become a slick car salesman. In the showroom sequences and in a really odd nightclub scene he does a drab imitation of Jerry Lewis’ “Nutty Professor” metamorphosis, and we’re supposed to believe it makes him liked and successful, though he’s actually a jerk.

Another part of his plot to win Stephanie from her rotter of a boyfriend Gale (Joe Rogan, insufferable) is to attend his brother’s wedding with another gal to make his old girlfriend jealous—the zoo’s sweet vet Kate (Rosario Dawson). That provides an opportunity for a frantically unfunny dance-off and a confrontation with Gale that’s even worse. For some reason it all makes both women interested in Griffin—something that, even more than the fact that the animals talk, place the movie firmly within the fantasy category. We all know which of the two he’s going to wind up with, and we’re proven right in one of those “rush to the airport” finales that goes on far too long (as does the entire picture, which logs in at a punishing 101 minutes).

Apart from Bibb, Dawson and Rogan, all of whom are badly used here, the supporting cast also includes Donnie Wahlberg as the mean keeper counterpart to Griffin and Ken Jeong as the creepily lascivious reptile keeper. He tones things down from his “Hangover” turns but remains a crude caricature. Technically the animal effects are fine but in no way special; this sort of thing has become so common that unless the lines such quasi-human critters utter are good, it earns little more than a yawn. Frank Coraci’s direction is pedestrian at best, while the physical production is mediocre (the urban landscape behind the zoo in some establishing shots looks like a cheap backdrop). And the movie too often falls into the ever-more-common trap of having characters sing and dance along to familiar pop tunes—a device that’s become as much a proof of lazy screenwriting as long bouts of introductory narration.

When a talking-animal bomb like the Eddie Murphy “Dr. Dolittle” or “Furry Vengeance” or “Zookeeper” comes along, you might be tempted to muse that “Babe,” as wonderful has it was, has a lot to answer for. It started the trend, after all. But it also showed how it should be done. It’s a lesson this stinker learned nothing from.