He spins a piece of magical realism, a house propelled by balloons. This is the idea of Carl Fredricksen, who's inspired by Charles Muntz (Christopher Plummer), a real crackerjack explorer that has seen South America and Paradise Falls. Fredricksen is a fanboy, and as he is going about his idolatry of his favorite adventurer, he meets a young girl also sharing his obsession named Ellie, who has a Cher-like set of hair and a possibly even more avid passion for Muntz. To make a long story short, the two get married, and dream of making it to Paradise Falls, but Ellie passes on and Carl (now played as an old man by Ed Asner in his Pixar debut) now becomes a recluse of sorts. Since as a young boy he made a promise to get eventually to South America, Carl vows to keep it true.
Just as he's about to be carted off to some cliche retirement home, he takes off with his house, using the balloons to keep him off the ground (they have a previous significance-Carl was a balloon vendor at a zoo). It's sort of like an Americanized, animated knockoff of "Danny Deckchair" which I doubt Bob Peterson ever saw or heard about. Anyways, literally like 90 seconds after he takes off, he's interrupted from his relaxation by boy scout wilderness explorer cliche animated youngling Russell (Jordan Nagai). He unfortunately makes the plot utterly predictable. The film's major plot point can be seen much before it's intended to. So, the two travelers make it to Paradise Falls but land on the other side. Fredricksen wants to be right on the edge of the falls, so the two begin a semi-epic journey through the tropical undergrowth and bump into two major characters: Kevin, some sort of bizarre, toucan-esque bird that makes a pretty funny call, and Dug (Peterson's voice), a collared, somewhat sadistic but overall amusing dog. Dug is trying to catch the bird, and bring it back to Muntz, who's been staking out in the jungle, searching for it all the time. Why? Because it signifies his legitimacy, since he originally brought back a skeleton and no one believed that he had found a new species.
I won't reveal much more, but just let you know that it all eventually dissolves into misguided chase scenes and underwhelming CGI animation, not unlike the special effects in the "Star Trek" film (sort of agreeing with Ebert, who has a distaste for big CGI and "Star Trek" but also loved this movie). Pixar, too focused on the little details, seems to forget that a film needs some sort of hook or point of interest besides little references and such. Fredricksen's quest to get from one side of Paradise Falls to the other is actually quite pointless, or at least it becomes pointless. It seems like some sort of vehicle to drive the film onwards. This shows all the more that the film is really, really rushed. Maybe it was to get it to Cannes where it would be the first animated film to open (as the Playlist said, "Inglourious Basterds" was the very same, so that's how I got this idea).
The editing is where the film most goes wrong. It might have been trying to mimic the 40's style (oh, right: the film's coy ideas of that decade are really quite cliche), but altogether it comes off really clipped. There is too much emphasis on the transitions (which grow extremely strained in the closing minutes) and not enough on less hyperkinetic cutting. As I've said before, the last 20 minutes make almost absolutely no sense and would be considered purely rushed if not for the sentimental hooks that are provided. It seems in the end that the whole structure is scrapped just for a couple of throwaway jokes and such. In the end, "Up" is the Pixar movie with the least amount of effort altogether. There were some nice details, but it still seems that Pixar is trying to tinker with success. C