A skewering of the original story about a fearful fowl who caused a town uproar when an acorn fell on his head and he mistook it for the sky falling, "Chicken Little" uses that classic fable as a jumping-off point for a tried-and-true underdog story. Sending out the wise adages to always be yourself and that you can do whatever you set your mind to, this rainbow-colored animated family film has enough sly jokes and clean adult humor to entertain grown-ups. Children, however, are clearly the target audience, and they will be delighted by the cute-as-a-button protagonist and a comedy/sci-fi plot that offers some pint-sized thrills without ever getting too scary.

Set on an alternate vision of Earth where all the inhabitants are animals (the shot near the beginning of a human Harrison Ford in "Raiders of the Lost Ark" doesn't really make sense in this context, but never mind), Chicken Little (voiced by Zach Braff) is the pint-sized butt of jokes in his town after confusing a falling acorn for the end of the world. So popular is the story, gaining worldwide media coverage, that a movie based on the incident is headed into production. After Chicken Little tries out for the school's baseball team in hopes of making his widowed father (Garry Marshall) proud, a stroke of determination allows him to hit the winning run of the championship game. No sooner does he get the glory and respect he has always yearned for does a real-life UFO land near his house. With friends Ugly Duckling (Joan Cusack), Runt the Pig (Steve Zahn), and the silent Fish Out of Water there to back him up on the claim, Chicken Little sets out to warn the town of an alien invasion. It turns out that convincing them he is telling the truth this time isn't so easy.

Directed by Mark Dindal (2000's "The Emperor's New Groove"), "Chicken Little" is a minor animated effort, but breezy and enjoyable all the same. The movie is less unctuous than 2004's annoying "Shark Tale," not as innovative as 2001's "Shrek" and 2004's "Shrek 2," and about on the same level as 2005's "Valiant." The plot has trouble obtaining focus at the onset—it's not really clear where the movie is going until the halfway point—but then transforms into a "War of the Worlds" rendition for kids. So similar is the alien invasion angle to the H.G. Wells novel, made all the more glaring by the recent adaptation by Steven Spielberg and complete with tentacled alien ships and zapper rays seemingly obliterating the animal-people into thin air, that plagiarism is originally considered a possibility. But then, proving that they are one step ahead of the audience, screenwriters Steve Bencich and Ron J. Friedman toss in a direct reference to "War of the Worlds" and all is forgiven.

Chicken Little, voiced by a well-cast Zach Braff (2004's "Garden State"), makes for an affably adorable hero, while Joan Cusack (2005's "Ice Princess") as Ugly Duckling, Steve Zahn (2003's "Daddy Day Care") as Runt, Garry Marshall (2002's "Orange County") as Chicken Little's father, and Amy Sedaris (2002's "Maid in Manhattan") as adversarial classmate Foxy Loxy, lend their own offbeat charms to the other lead roles. Don Knotts (1998's "Pleasantville") gets to voice the funniest character, Mayor Turkey Lurkey. A sharp send-up of politicians who can't think or talk for themselves, Mayor Lurkey recites his dialogue off of cue cards he strategically has placed in front of him at all times.

As far as its place in the kid-friendly animated arena, "Chicken Little" could have used more concentrated plotting and a more imposing villainous force. It is proven early on during the invasion that the aliens aren't so much hostile as they simply want back their son, who was accidentally left behind, so any threat dries up pretty quickly. At 78 minutes, the film is also over too soon to make the impression it wants to. If "Chicken Little" is not a new Disney classic, it is still mostly a success all the same. There is a sweetness in the way Chicken Little remains resourceful even when placed in a shadow of doubt and ridicule from his peers and elders, and his rise back to the top is one that young audience members will especially get involved in and root for. The soundtrack also keeps things briskly moving along, with a great new Barenaked Ladies track, "One Little Slip," that perfectly encapsulates Chicken Little's plight. "Chicken Little" may be a slight entertainment, but like the diminutive title character, the movie is good-natured, hard to dislike, and always able to recover after any stumble.