‘Jennifer’s Body’: Girl Trouble, By Kurt Loder

Megan Fox vs. Amanda Seyfried in a biting new comedy.

Just as he’s about to rip the beautiful Jennifer’s tightly bound body to shreds with a knife, hunky young Nikolai tries to tell her why. Nikolai is the lead singer of an indie band called Low Shoulder. They’re desperate to make it big — to be the next Maroon 5! But the world is awash in indie bands, so it’s hard. “There are so many of us,” he says, “and we’re all so cute. … Satan is our only hope.” In the group’s quest for diabolic new management, Nikolai has downloaded a Satanic ritual off the Internet. All that’s required is a virgin sacrifice. Unfortunately, he’s picked the wrong girl: Jennifer’s days of sexual innocence are far behind her. (“I’m not even a backdoor virgin,” she later admits.) So the ritual goes seriously wrong. Instead of leaving Jennifer dead, it transforms her into a snaky-eyed, flesh-eating demon. Oops.

The negative early reviews with which “Jennifer’s Body” has been greeted are puzzling. Critics seem irked that the picture’s not a full-on horror film or a straight teen comedy or a familiar satirical combination of the two. But the movie has other intentions: It’s really about the social horrors of high school for adolescent girls (the guys on hand are clueless bystanders). And with a script by Diablo Cody (her first since the Oscar-winning “Juno”), the picture has a tone — smart and slashingly sarcastic — that’s all its own. It’s actually kind of brilliant.

Picking Megan Fox to play Jennifer was a sharp move — who better to portray this cold-hearted tease and all-around bitch on wheels? (“What’s wrong with you?” Jennifer asks a classmate. “Besides the obvious surface flaws?”) And Amanda Seyfried — tamping down her sunny cuteness with bookworm glasses and pulled-back hair — is just right as Jennifer’s inevitably nerdy best friend, Needy. Jennifer was a monster even before her Satanic transformation at the hands of Nikolai (Adam Brody), but Needy has remained loyal to her childhood pal. When Jennifer starts munching on their fellow students, though, Needy has to seriously rethink their relationship.

Director Karyn Kusama (“Aeon Flux”) has given the picture a rich, lustrous look, and there are some wonderfully well-edited scenes, like the back-and-forth montage in which we see Needy having sweet first-time sex with her boyfriend, Chip (Johnny Simmons), while Jennifer has her bloody way with the school’s timid, lip-ringed goth guy (Kyle Gallner) — who soon learns what goth is really all about.

The movie has a generous ration of gore; but Kusama — possibly with input from “Juno” director Jason Reitman, who produced the film with several associates — maintains smooth control over the picture’s diverse genre elements. So, while Fox suggests nudity even when fully-clothed, nobody gets naked in any really ogle-worthy way. And there’s a scene in which Jennifer lures the school’s star linebacker out into the moonlit woods (reaching into his pants for a purpose very different from what the big lug is expecting) that primes us for some vintage flesh-rending; but then an audience of cute little forest critters gathers around to watch, and suddenly we’re somewhere else entirely.

The picture gets a powerful kick from its well-chosen soundtrack (Silversun Pickups, All Time Low, even Hole — although not that band’s own “Jennifer’s Body”). But it’s Cody’s pop smarts that keep the movie really bubbling. She knows all about bands and boys, and she never hits a bum note. As Nikolai’s Satanic ritual is about to get under way, he tells the helpless Jennifer to look on the bright side. “Maybe we’ll write a song about you,” he says. Perfect.

Don’t miss Kurt Loder’s reviews of “Beyond a Reasonable Doubt,” “Whiteout,” “The Informant!” and “The Burning Plain,” also in theaters this week.

Check out everything we’ve got on “Jennifer’s Body.”

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