The folks at Nickelodeon seem to have the formula down when it comes to taking an animated kids' TV show and expanding it to the big screen. They scored with the Rugrats, and they score here again. Arnold, a football-headed do-gooder with a Harpo Marx coif (voiced by Spencer Klein), finds himself in a tizzy when the head of a mega-conglomerate (Paul Sorvino) proposes bulldozing the neighborhood to make way for "progress." The mayor supports the scheme, but fourth-grade Arnold urges everyone not to sell out while he tries to infiltrate the pernicious corporation, find the smoking gun, and save the 'hood.

The film moves along breezily and is packed with many a fun-filled reference, from film (Speed, Men in Black, Mission: Impossible) to history/politics (Watergate, the American Revolution, and the way Sorvino's CEO sounds eerily like Ronald Reagan). The direction by Tuck Tucker is tight, the moral lessoning is relevant and on the mark, and the supporting characters, most notably Arnold's sewer-crawling granny (Tress MacNeille), notch their high jinks at the most appropriate moments. At the Apple Valley, Entertainment, Flagship, Holiday, Hoyts, Showcase, and Tri-Boro cinemas.