Anita knows that something is very wrong when her best friend, Jennifer, turns up at her house after a night of partying with a rock band, splattered with blood, barfing up black goo and raiding the refrigerator to chomp into a rotisserie chicken.

It’s a goofy moment in Jennifer’s Body, a grisly horror-comedy that tries to be a sort of cross between Carrie and Heathers, but could use more jump-out-of-your-seats frights and a lot more laughs. I was hoping for something as scary-funny as Drag Me to Hell was earlier this year, but Jennifer’s Body never quite reaches the high notes of that bit of manic insanity.

Much of the terror in the story of a girl who becomes possessed by a demon and goes on a vampirish killing spree, chowing down on her classmates to feed the deep-seated hunger inside her, is telegraphed ahead of time by director Karyn Kusama. Where’s the surprise? Where’s the suspense? Diablo Cody, who won an Academy Award for the offbeat unwed-teen-mother comedy-drama Juno, goes for the funny bone with pointed lines and sharp characters, but more often than not she hits the jugular vein.

The film opens in a mental hospital where Anita is now an inmate. “I used to be normal, well as normal as any teenage girl under the influence of adolescent hormones,” she tells us in voiceover. Then we see, in flashback, why Anita is where she is and why Jennifer arrived at her house late one night covered in blood.

Anita (Amanda Seyfried from Mamma Mia!) is a bit dowdy and cautious, the polar opposite of her best friend Jennifer (Megan Fox of The Transformers movies), who is flirty and sexy and brazen in her approach to boys of all ages. Her nickname for Anita is the unflattering “Needy,” although Anita seems the more practical of the two. And yet they have remained friends ever since their sandbox days.

When Jennifer catches the eye of Nikolai (Adam Brody of The O.C.), lead singer in a rock band playing at a local low-rent nightspot, she gets more than she had bargained for.

(At this point I must caution Rhode Islanders who plan on seeing this film that the most disturbing part of the movie is not Jennifer’s go-for-the-throat zombie-ish appetite nor the grisly shots of her victims whom she has turned into mincemeat. Rather, the most unsettling moments come at the not-very-glamorous nightclub when a fire starts behind the band that is performing on stage. The fire quickly spreads, turning into a raging inferno from which few make it out alive. The parallels to The Station nightclub fire are unmistakable, right down to the next-day scene of the smoldering aftermath. But the fire in Jennifer’s Body is played offhandedly and some of the survivors, most notably Jennifer, react to it with casual indifference. Although it is just a plot device in Jennifer’s Body, the sequence will dredge up old wounds and nightmares locally.)

Despite some amusing asides and a few surprises, much of the rest of the film seems anticlimactic with Jennifer playing the temptress in order to get close to some of her victims. Jennifer even hints to Needy, who isn’t sure what’s going on at first, that she might be interested in Needy’s sweet and unassuming boyfriend, Chip (Johnny Simmons).

There are some nutty moments in Jennifer’s Body that make it one of a kind –– forest animals arriving to watch Jennifer as she puts the make on the high school football star; Needy running across a grassy field in a flouncy red taffeta gown after she has a premonition of danger; a high school poster advertising Whatever Happened to Baby Jane?: The Musical.

But much of the film follows traditional horror movie rules: When Anita hears strange noises somewhere in the house, she of course opens doors to dark places to investigate.

The film seems aimed at the high school set with its spoof of teenage anxieties and its spoof of high school life. Yet its R rating –– for sex, profanity and grisly violence –– may cut out the people who would most want to see it.

** 1/2Jennifer’s Body

Starring: Megan Fox, Amanda Seyfried, Adam Brody, Jimmy Simmons.

Rated: R, contains violence, grisly images, sex, profanity, adult themes.

mjanuson@projo.com