I'm a little annoyed with Up right now, because it made me cry in the first 10 minutes. Crying at the end of a movie is easier to hide -- you can mutter about allergies or how too much computer time makes your eyes red. But crying at the beginning of the movie makes you feel like an awfully sappy wuss. Thank goodness I had big ol' 3-D glasses on, which at least managed to hide any telltale traces of weakness ... until I cried again at the end, damn it.

Up is the latest film from Pixar, and this time the main character is not a robot or rat or monster, but rather a little old man who looks like Spencer Tracy and occasionally growls like Clint Eastwood in Gran Torino. After his wife dies, Carl Fredericksen (Ed Asner) faces a lonely life ahead, possibly in a retirement community. He decides to have the adventure that he and his wife always dreamed of, and sets out for the quasi-legendary Paradise Falls in South America. His method of travel? The family home, lifted by an amazing canopy of balloons. However, he isn't alone ... he's inadvertently picked up an enthusiastic 8-year-old Wilderness Explorer, Russell (Jordan Nagai), who only wants to help.

As the movie progresses, Carl's house stops being a means for escape and adventure, and turns into a burden that the two explorers have to drag around with them. And the movie shifts from a sweet and slightly fantastic story about how an older man copes with loneliness and regret, into a comic action-adventure tale with a setting and characters that would be right at home in Warner Bros. cartoons, especially the "Road Runner" series. Only instead of Wile E. Coyote, Carl and Russell find the explorer who inspired Carl when he was Russell's age, Charles Muntz (Christopher Plummer).

Up moves smoothly from romance to drama to fantasy to comedy to action-adventure and then back to sentimental drama again, without jolting your emotions around too much. The sentimental parts are sweet but not cloying or overdone. On the other hand, the Carl-Russell relationship seemed a little too familiar to me, something we've encountered for decades, from "Dennis the Menace" to Bad Santa, without offering much that is new. I also would have liked Muntz to be a little less two-dimensional, so to speak. However, as a friend pointed out, Carl and Muntz have a wonderful dynamic that may remind you of not only Spencer Tracy but Kirk Douglas, together at last.

Co-director Pete Docter also directed Monsters, Inc., another Pixar comedy with some sweet moments and even a few that have you complaining about the allergies and the way that screen glare can make your eyes water. Bob Peterson, who contributed to scripts for Finding Nemo and other Pixar movies, co-directed and wrote the screenplay and voices one of the dogs. Pixar fans will appreciate the little touches typical of the studio's films -- of course John Ratzenberger has a role, this time as a construction worker, and there are a number of quick visual jokes that are impossible to catch in a single viewing.

It goes without saying, as it has for even the weaker Pixar entries, that the movie looks gorgeous. I saw Up in 3-D, found the 3-D effects to be very subtle ... so subtle that at times I wondered if parts of the film had been rendered into 3-D at all. The 3-D occasionally adds some depth of field that enhances the overall look of the movie, but for the most part you could do without it and not miss anything. I'm a little sorry that the one theater in town with 4K digital is only showing the movie in 3-D because I would love to see how a high-quality traditional screening fares in comparison.

Up is good enough to be included in arguments about which Pixar film is best, although I would still fight for Ratatouille, myself. Is Up a children's film with side jokes for adults, a family film, or a film that's made for grownups but has many elements that children also can enjoy? At times it seems to fit in any of these categories as well as others -- it would be a great date film -- but ultimately it boils down to being a very good movie that defies demographic categorization. In other words, if you're old enough to sit quietly through a feature film, go see it. (And bring tissues.)