WHEN BOILED DOWN, the Sundance hit Little Miss Sunshine reveals the bones of a Shirley Temple plot. The title is completely descriptive. Exactly as in Shirley's heyday, this comedy is about a bunch of depressed grouches sweetened up by the optimism and charm of a little girl. On the bright side, the lead Abigail Breslin (the daughter in Signs) isn't quite as unearthly as her model. Breslin's Olive doesn't have a coy, flirty moment—the kind of crowd-working that made Temple as appalling as she was famous. Behind her sizable eyeglasses, Breslin looks damp and a little slow. And when she dresses up for a beauty pageant, in silhouette her body looks like a jumbo lima bean.

Little Miss Sunshine's plot is typically Sundancian—take a fractured family to the desert and bond them—but directors Jonathan Dayton and Valerie Faris work harder on the comedy than the bonding. The family members are authentically ornery; they only meet at the dinner table to chomp on fast food chicken and to snarl at one another. They have a new lodger: an uncle on suicide watch, who just lost a job and a lover. Frank is played by a bearded Steve Carell, ever so much more funny as a supporting actor than as a lead.

The rest are a gang of comedic stereotypes, but let's be kind and call them archetypes. There's the old sinner of a granddad (Alan Arkin, irresistible and Oscar bound), and his seat mate, a little brother, dummied up and posing as a walking time bomb (Paul Dano). In the role of the alienated mom is Toni Collette. There are so many homely women in the world, and Collette plays them all. The dad (Greg Kinnear, naturally) is driving everyone into the poorhouse, hustling his nine-step "Refuse to Lose" seminars; just as naturally, since he's Kinnear, he loses. When the family is informed that frequent beauty-contest applicant Olive has been accepted into a show in Redondo Beach, Calif., they decide to drive out to give her a chance.

The road is arduous, the car is defective and there are bubbly character-acting bits to keep the comedy coming: Paula Newsome as a useless grief counselor and Julio Oscar Mechoso as a suave mechanic amused by the terrible plight of the van's gearbox. And—this rarely happens, especially in family comedies—the film has an actual finale, instead of a group hug. The children's beauty pageant is in monumentally bad taste, as if it had been guest-directed (that is, directed by Christopher Guest); happily, Olive tops it all. Watching Breslin float through this film is like one of those moments where you're bowled over by the obvious: gosh, having a sweet-tempered daughter around would really take the edge off of life.

The film looks a lot like one of the Vacation movies. It has inexplicable dramatic bits, like a moment where two men with a mutual past meet at a gas station in the middle of absolute nowhere. It sports Fox Network-level comic machinery, like a profane old man saying alarming things and the children repeating them. Ultimately, Little Miss Sunshine proves there are certain things in the movies that are never funny except when they are.

Little Miss Sunshine (R; 101 min.), directed by Jonathan Dayton and Valerie Faris, written by Michael Arndt, photographed by Tim Suhrstedt and starring Greg Kinnear and Toni Collette, opens Aug. 4 at the Aquarius in Palo Alto and CinéArts in Santana Row.

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