The humans are gone, but Scrat remains -- and that's probably all most Ice Age fans want to know anyway. The folks at Fox clearly realized that without the acorn-obsessed saber-toothed squirrel, no one would care about the ongoing adventures of the other animals.

The persistent little rodent gets plenty of screen time, popping up whenever things get dull elsewhere -- which happens with surprising regularity.

That's because Ice Age: The Meltdown features the lamest story of any CG-animated feature to date: The glaciers are melting, so all the animals must migrate to higher ground before the valley floods.

Migration doesn't exactly make for the most riveting entertainment, though it could be interesting if there were any peril involved -- say, if a significant number of the species actually died in the process (the best scene in the original featured a colony of dodos with a gift for expediting their own extinction).

Back in 2000, Disney's Dinosaur featured a remarkably similar survival-of-the-fittest setup. The fact that Ice Age: The Meltdown still manages to engage us while essentially recycling a bad story idea suggests how much fun the creators are able to have in the process.

Manny (Ray Romano) gets a love interest (Queen Latifah), an orphaned mammoth raised by possums who grows up thinking she's one of them. Sid the sloth (John Leguizamo) is dimwitted as ever, and Diego the smilodon (Denis Leary) is now all smiles and no teeth, afraid of water and apparently never hungry.

Scrat, meanwhile, is always hungry. Like Wile E. Coyote and his roadrunner traps or Yogi Bear with his picnic baskets, Scrat's struggle depends on never achieving his goal.

There's not much to Ice Age: The Meltdown, but it's enjoyable all the same. With films like this, plot serves its purpose on first viewing, but it's the amusing character moments that make it tolerable when the kids insist on watching it over and over on DVD down the road.

Here, the filmmakers would've been happy to spend the entire 90 minutes just riffing with the characters. The obstacles they face, I'm convinced, function less for the movie's benefit than as setup material for the tie-in video game (which serves an ever-growing financial role in an era of dwindling theatrical profits). From sliding down ice chutes to chasing possums to staying afloat in the flood, the movie seems to be organized in "levels" rather than scenes (not that Star Wars -- Episode III was any different).

If this trend continues, don't be surprised to see the next Ice Age sequel debut exclusively for PlayStation. It's moviegoing, not woolly mammoths, that's going extinct.

[as featured in The Miami Herald]