“There’s stuff that goes down there people should never see,” B-Rad (Jamie Kennedy), the white Jewish kid who’s determined to be a rapper, says of his upper-crust California home town at the beginning of this farce based on a sketch from Kennedy’s TV series. When one hears the line, he may well suspect that it will provide a perfect tag for the picture as a whole (just as you assume that an adamant rejection of the character’s admonition “Don’t be hatin'” will be the proper reaction to the flick), but happily that’s not entirely the case. “Malibu’s Most Wanted” is certainly a one-joke movie, but it’s not a bad joke; and though it never realizes its potential, with the level of inspiration paling ever further going down the home stretch, the picture winds up winded but still gasping for breath as it crosses the finish line. The best recent comparison is probably to “Undercover Brother,” which cleverly skewered both sides of the racial divide with surprising good humor. This effort isn’t nearly as smart or consistent, but it too is a comedy about the hood which will play well in multiplexes in the white suburbs. Whether that’s a good thing is a matter of debate, of course (and whether it will appeal to African-American audiences at all is doubtful). But its essentially good-natured foolishness isn’t all that hard to stomach, even if it’s essentially of sitcom caliber, with a feel-good denouement that salutes family, interracial amity, friendship and being true to yourself in a fashion almost calculated to make you wince. At least it’s not unremittingly gross or crude, the way most comedies aimed at adolescents are nowadays.

The linchpin of the plot is that B-Rad’s distant but well-meaning father Bill Gluckman (Ryan O’Neal) is running for governor, and the boy’s embarrassing behavior threatens his campaign. To solve the problem, Bill’s Machiavellian campaign manager (Blair Underwood) concocts a scheme to force B-Rad to abandon his hip-hop persona and revert to nice-kid Brad. He hires two actors (Taye Diggs and Anthony Anderson) to pretend to be gangstas, car-jack the fellow and give him such a frightening taste of the real hood that he’ll literally be scared back into comfortable “whiteness.” Needless to say, the plot backfires, but in doing so it actually works to Bill’s political benefit. And in the process B-Rad finds romance with Shondra (Regina Hall), a strong-willed girl with dreams of her own.

Curiously enough, Kennedy’s character is the least interesting element in the movie. B-Rad is a clownish figure whose one-note antics are never as ingratiating as the makers intend. When he takes the stage for a rap contest that’s supposed to send up the ones Eminem did in “8 Mile,” for example, the bit falls flat due to the limp writing. (Indeed, the only funny gag comes when B- Rad shows that, when it comes to being vocal while watching a movie, he’s totally transformed.) In short, the idea of satirizing rich white kids who pose as gangstas is a potentially rich comic vein that Kennedy barely scratches. What makes the picture work to a modest degree is the counterpart it offers to B-Rad in African-Americans who deplore the gangsta culture and aim to prosper in white society. Underwood’s manipulative Tom Gibbsons is one example (an Uncle Tom if ever one existed), but by far the funniest are Sean (Diggs) and PJ (Anderson), the would- be thespians who find themselves constantly compelled to accept parts that are the very denial of what they aspire to. When Diggs delivers, with his clipped, precise diction, a complaint about having to play a thug once again, the self-referential character of the bit adds a nice layer to the humor.

Unfortunately, nothing else in the flick is equally amusing. It’s like old home week seeing O’Neal again (and Bo Derek as his wife), and the jokey campaign commercials he appears in are lowbrow fun, but little else is done with his bland character. Hall has spirit, but she too is poorly used, and though Snoop Dog is listed in the cast, he’s only vocally present, providing the voice of a chatty rat in one of the picture’s more surrealistic moments. The slapstick members of B-Rad’s “gang” (Kal Penn, co-writer Nick Swardson and Keili Lefkovitz) don’t quite make it as a trio of stooges, either. Technically the movie is pretty cheesy, but it seems to exult in the tackiness; John Whitesell certainly moves a rung up the directorial ladder here after helming the deplorable “See Spot Run,” and he keeps things moving reasonably well; but that’s about all one can say of his contribution.

“Malibu’s Most Wanted” is no more than a benign time-waster, not consistently funny enough to recommend, but the fact that it isn’t the horror its trailers suggested is itself a relief. Don’t bother with the out-takes that accompany the final credits, though; they’re lamer than the least amusing parts of the actual movie.