Three 15-year-old girls sit watching a porno, discussing their future. Randa, wearing an Islamic Hijab, explains that she wants to be a doctor to “help poor people” — though Kimberly, the trio’s top dog, ice queen extraordinaire, scolds her friend. Randa should want to be in show business instead of worrying about the poor: “Actresses appear in films that have important social messages.”

This sly self-effacement in the new black comedy “Pretty Persuasion” implies that the film itself has something important to say. But marred by a muddled script and uneven cinematography, “Persuasion” never quite hits the social satire G-spot. But it can come pretty damn close.

“Persuasion” begins in that touchstone of adolescent black comedy: the prep school. Kimberly Joyce (Evan Rachel Wood) is the star pupil of Roxbury Academy in Beverly Hills (where else?). Bored with the school and aching for fame, Kimberly decides to frame her drama teacher Percy Anderson for sexual assault. Using her friends and enemies as pawns, she engineers a charade with the unknowing help of local lesbian anchorwoman Emily Klein (Jane Krakowski).

At its best, the film crackles with taboo humor. The gauntlet for bold raunchiness belongs to Kimberly’s Jew-hating “it isn’t racism if it’s true” father Hank Joyce (James Woods), who enjoys masturbating in tiger stripe underwear. For the mental set, these jokes are well-crafted little demons — they rely on the reaction of the other characters to tip the audience away from outrage towards laughter.

A sample: Kimberly one-ups John Cusack’s famous scene in “High Fidelity” with a top-three list of races she “would most like to be if she wasn’t white.”

As Kimberly, Wood (“Thirteen”) channels the glory days of Christina Ricci, delivering her lines with blood-chillingly false sincerity. But unlike young Ricci, Wood oozes sex; with the slightest of eyebrow raises she can make even the most mundane sentences sound like the naughtiest come-ons in the world. She manages to walk the line between camp and realism; she takes herself seriously.

Woods decides to go the direction of farce with his take on Kimberly’s cocaine-sniffing, pot-bellied father. Eyes bulging, he rampages through the film as if it were a bad SNL sketch that just won’t end. Like Christopher Walken, he seems out of tune with everything around him — but, alas, he doesn’t have Walken’s terrifying presence to lend the necessary gravity to his ravings.

Selma Blair, who has become a fixture in this genre, gives a standard performance as Anderson’s girlish wife. At first she seems to have graduated to a more mature role, but by the time Mr. Anderson dresses her up as a schoolgirl, it’s all by the numbers. There’s nowhere to take your career after mastering the slightly goofy drunken sex scene, but she manages to be a good sport throughout.

As a black comedy, “Pretty Persuasion” does nothing new. Many of its scenes frankly seem cherry-picked from a slew of better films (“Heathers,” “Election,” or “Igby Goes Down”), though there indeed are some bright moments of creativity. When Kimberly is cast as Anne Frank in the school play, she holds up her copy of the Diary, and we see Anne’s smiling, unguarded picture under Kimberly’s icy gaze. Here “Pretty” is at its most unnerving and funny.

Perhaps director Marcos Siega deserves most of the blame for the film’s shortcomings — namely, its unoriginality. With only one other film to his name (not counting four sub-par Weezer videos), Siega doesn’t seem to be quite on top of his material. Multiple shots are terribly framed — one that is filmed through a wall calls so much attention to its awkward positioning that it is hard to pay attention to the dialogue. And the film’s fussy score doesn’t make matters any better.

If seen as social satire, this petite “To Die For” is woefully incomplete. Little can be learned from our anti-heroine, who is merely a rough sketch of a human being, a Frankenstein-like amalgamation of genius and cold-bloodedness. We are left with only the slightly more human characters, Kimberly’s incompetent father, the victimized Mr. Anderson, and the manipulated anchorwoman. But these people all turn out to be morally lax, for various reasons that are mostly unexplored. One possible lesson could be that Mr. Anderson’s semi-destruction at the hands of his false accusers is wrong, but his latent fetish for schoolgirls makes it hard for us to accept him as a martyr.

Behind the film’s outrageous story and lewd gimmicks is the reactionary point that kids today aren’t raised correctly. But what’s the point of that? Good parents can raise bad kids, and inept or lazy mothers can bring up little angels — at least films like “Thirteen” are bold enough to explore why. “Pretty Persuasion” contents itself with pointing out an obvious social problem, and sitting on its laurels from there on. Thankfully, it also happens to be funny (though perhaps not to the Anti-Defamation League) along the way.