Early on in “Ice Age: Continental Drift,” the animated franchise’s fourth entry, John Leguizamo’s Sid the sloth has a quick, funny aside about the dinosaur-themed preceding installment. “It didn’t make sense,” he says in his familiar goofball lisp. “But it sure was exciting.”
The line might as well be the filmmakers’ cheery mantra for the entire enterprise here, as they drop Sid, Manny the mammoth (Ray Romano), and sabretooth Diego (Denis Leary) into a pirate tale that couldn’t feel any more arbitrarily conceived. And who’s got time to give the prehistoric trio genuinely engaging new business to tend to when there’s a whole crew, literally, of new characters to introduce? It makes you wonder if the series’ animators, who took time out for “Rio” just before this, aren’t so secretly yearning to sail different creative waters.
The story opens with acorn-fixated Scrat the squirrel wreaking planet-core havoc that comically ends the world as the group knows it. Put another way: goodbye, Pangea. (Oh, Scrat, you’re the closest thing we’ve got these days to classic Looney Tunes.) Soon, Manny, Sid, Diego, and Sid’s tagalong granny (Wanda Sykes, sassing exhaustingly) find themselves cast adrift on a broken-off ice shelf, violently knocked about in a sequence that’s a 3-D dazzler. Manny gives his paternal neuroticism a rest, the group bickers with renewed, situationally charged zing, and they generally remind us why we’ve enjoyed their bonding and bumbling for a decade.
Their goal is to get back to Manny’s mate, Ellie (Queen Latifah), and their restless-teen baby girl, Peaches (Keke Palmer). But first they have to spend a while – a looong while – tangling with those pirates, notably simian Captain Gutt (Peter Dinklage, “Game of Thrones”) and his tigress first mate, Shira (Jennifer Lopez).
Dinklage works hard, and his gold-toothed monkey mariner is amusingly designed, but it’s not nearly enough to shake the sense that we’re watching elaborate filler. (J. Lo’s conflicted character is completely generic, and wedged-in bit players like Nicki Minaj and Drake are similarly disposable.) When Manny and pals finally head off in a chiseled-glacier getaway ship – another swell visual sequence, incidentally, complete with trippy Sirens – it feels less like they’re escaping the bad guys than a bad middle act.
Speaking of arbitrary, “Ice Age” corporate stablemate “The Simpsons” supplies an opening short, a 3-D look at baby Maggie’s misunderstood life at day care. It’s weird, wonderful, and virtually wordless. It’s also a welcome throwback to the days when “The Simpsons” had more sentiment at its core, and wasn’t so much about the latest batch of newbie Ivy League writers taking their cues from “Family Guy.”
Tom Russo can be reached at trusso2222@gmail.com. 
