Up answers the question that every kid with a balloon has pondered at some time: If you had a lot of balloons, could you fly? Up answers in the affirmative, confirming every kid's suspicions. It takes a whole lot of balloons, of course - especially if you, like Carl Fredericksen, want to take your entire house aloft with you. Carl is a retired balloon salesman, so he'd know how to do such things, naturally.

And so would the animators at Pixar, whose latest film soars and swoops and sails, but also keeps its feet (both metaphorical and literal) on the ground. Carl's house is ripped from its foundations by thousands of balloons following their lofty, balloony imperatives, but it is Carl who needs uplifting. With his squat frame, square head and black square glasses, he looks like he's been squashed from above - or maybe gravity has pulled him downward over the years.

It wasn't always so; as Up begins, he's a kid, dazzled by newsreels of heroic aviator and explorer Charles Muntz. Carl's not alone in his hero worship and quest for airborne excitement: Newfound friend Ellie shares his spirit of adventure and wanderlust. In a lovely silent montage, Up follows Carl and Ellie through marriage and through the years, as worldly concerns, heartbreaks and everyday setbacks keep them tethered to their lovely old house until...there's just Carl, and a dream unfulfilled. Enter balloons, and a crazy, quixotic quest to plant that house in an exotic faraway land.

And enter Russell (voiced by Jordan Nagai), an eager Wilderness Explorer scout who is determined to earn his final merit badge for assisting the elderly. He decides that Carl (Ed Asner at his gruffest) is the elder he is going to assist, but curmudgeonly Carl thinks otherwise. Russell is an unwitting stowaway on Carl's great balloon adventure. Will Carl and Russell discover that they can assist each other? Do balloons wanna fly?

Co-written and directed by Pete Docter and Bob Peterson, Up is the first Pixar movie to be released in 3-D. The 3-D effects are quite subtle; if you don't want to schlep to a 3-D theater, you won't miss much, and you'll still get an eyeful of beautifully rendered animation and, more importantly, characters with real depth. It's been 14 years since Pixar dazzled everyone with its groundbreaking computer animation in Toy Story. It's actually a little late jumping on the 3-D bandwagon, but 3-D is the new "It" tech in movies; and although Pixar has embraced it (promising that all of their films will be in 3-D from now on), it has not abandoned their core commitment to great storytelling and characters as real (and in many cases realer) than any that you'll find in a live-action movie.

The great innovation in Up is subtle: The emotional expressiveness of the characters is quite exquisite. Pixar has never embraced photorealism in creating human characters (which has never yet succeeded in being anything but creepy anyway), but its cartoonishly rendered humans are real in every other way. They have inner lives and emotions, and all of that is visible and evident in their faces, in their body language, in their voices. In Up, the richness of inner space has been beautifully rendered and fully realized in a story with enough specificity and depth to engage adults, and enough simplicity, excitement and adventure to captivate all the little Russells in the audience, too.

Carl is old. He feels old, he looks old, he walks with a cane and has to work the kinks out of his old bones in the morning. He's an old crank, too: gruff and grumbly, and not very appreciative of the plucky, nerdy kid who has tagged along on his quest. Russell's an egg-shaped hindrance in the way of all kids who don't live by the clock (not even the old lifespan clock that Carl no doubt hears ticking) and who obey the biological imperative to leave no stone unturned, no animal unrescued and no tiny thing unexplored. He's all enthusiasm and hope and high spirits (and needy, and not very cool).

Carl and Russell aren't the only fully dimensional characters in Up; there's also a big flightless bird who doesn't talk, and a dog named Dug who does, thanks to an electronic collar/universal translator that gives voice to Dug's every thought. Dug (voiced by Peterson) is not a deep thinker, but he's loyal and true, even when he's confused. Dug's a dog in need of a master as good and generous as he is; Russell needs a grandfather, and maybe a hug; Carl needs a swift kick in the butt and a tug at his shrunken old heartstrings (and as he drags his barely airborne house through the jungle, he increasingly needs to let go of his past). They all get more adventure than they bargained for when an unexpected villain turns up.

A square old man and a kid who isn't sassy or smart-alecky or snarky starring in a movie? Not exactly action-figure-ready, are they? It's almost enough to make you think that those Pixar folks are more interested in making good movies than in turning a quick buck. Huh. Imagine that.