"Make it fresh," Alex the Lion advises his best buddy, Marty the Zebra, when trying to entertain crowds at the Central Park Zoo.

Those are words of wisdom the makers of "Madagascar" should have followed, too.

The latest computer-animated extravaganza from DreamWorks is certainly an improvement over last year's desperate "Shark Tale," but it's not as crisp start-to-finish as the "Shrek" movies. And it falls into the same trap as so many films of this genre (with the notable exception of "The Incredibles"): In an effort to seem hip and high-energy with a litany of pop-culture references, the writing (from a team of four) instead comes off as hackneyed and lazy.

In the span of a 30-minute television show like "The Family Guy," this approach that can be hilariously effective. Over an entire feature film ? even one that's just 86 minutes long ? it feels like a stretch.

So when Alex (voiced by Ben Stiller), Marty (an exuberant Chris Rock), Melman the hypochondriac giraffe (a perfectly cast David Schwimmer) and Gloria the no-nonsense hippo (Jada Pinkett Smith) leave the safety of the zoo and inadvertently end up on the shores of Madagascar, there are allusions to everything from "American Beauty" and "Chariots of Fire" to "Planet of the Apes" and "The Twilight Zone." One joke even combines riffs on "Cast Away" and "Caddyshack" in the same breath.

Some of the gags in the film from director-writers Eric Darnell ("Antz") and Tom McGrath ("The Ren & Stimpy Show") are admittedly laugh-out-loud funny. Others fall flat.

All of them, of course, are intended for the adults in the audience and will sail right over the tiny heads of the kids, who will be captivated by the colourful, hyperactive characters.

See, the animals in "Madagascar" are more animated than the animated movie creatures we've seen over the last few years. That's because they harken to the slapstick style of those old Looney Toons cartoons ? a technique known as squash and stretch, which was easy to do by hand but is now much harder to do with computers.

(The backgrounds, meanwhile, are truly wondrous, from an evocatively detailed recreation of Grand Central Terminal to waves that lap on the beach so convincingly, you want to stick your toe in the water.)

Going old-school in this fashion is sort of a novel aesthetic, though it can get a tad dizzying in its frenetic spirit.

The lemurs that populate the island, for example, jump up and down with an enthusiasm that makes the Ewoks look lethargic at the end of "Return of the Jedi." (Oops, sorry ? Episode VI.)

King Julien the 13th is their self-appointed, party-boy leader ? and as voiced by the multitalented Sacha Baron Cohen, he's somewhere in between Borat and Bruno in Cohen's repertoire of characters on "Da Ali G Show." He's sorta Indian and sorta French and slightly gay but totally inept ? and fun to watch.

But it's another group of tiny creatures who steal the show: the penguins, whose leader is the gruff goomba Skipper (voiced by the McGrath, half of the film's writing-directing duo). They execute an efficient plan to escape from the zoo and return to Antarctica, only to realise that they hate it.

The foursome from New York realise they also miss the comforts of their pampered, structured life back home, and they all adapt in various ways. (By this point the movie is really dragging, and has little of the snap that made the dialogue so much fun in the beginning.)

Gloria works in an organised manner to flag down a ship (and the idea of the petite Pinkett Smith playing a big ol' hippo is amusing in itself). Melman is sure he's going to die without his medication. Marty builds an elaborate hut on the beach.

But Alex completely loses it in the throes of hunger, and envisions all the animals around him as juicy steaks ? even his friends.

The other inhabitants could have voted Alex off the island, but in an unusual show of restraint, the filmmakers refrained from throwing in a "Survivor" reference.

"Madagascar," is rated PG.

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