Nerdy and needy are neat in 'Jennifer's Body'

Word on the street is that Megan Fox stars in Karyn Kusama's horror film "Jennifer's Body," scripted by Diablo "Juno" Cody. Nope. Fox and her lip gloss move through the movie like a special effect, jeans hanging on to her hips for dear life, and she's a force to be reckoned with — but this movie belongs, hands down, to Amanda Seyfried. Score one for nerdy sidekicks everywhere.

Fox is high-school princess Jennifer, Seyfried is her bespectacled pal Needy (short for Anita, and a little too spot on).

Though Jennifer has long ago risen far above Needy's social circle, they've been friends since childhood and now maintain a tricky dynamic: Jennifer, who's so self-absorbed she has a picture of herself on her dressing table, likes having Needy around for the attention and the lack of competition; Needy is in awe of Jennifer's effortless (if bitchy) social skills. (Note the funny, subtle way in which Needy's clothes, while not wildly different from Jennifer's, are terribly, terribly wrong.)

When the girls go to a concert, performed by a group of guys who turn out to be "basically agents of Satan with really awesome haircuts," all goes awry quickly.

Jennifer is soon spouting blood and bile and craving live flesh, Needy is terrified yet unable to help, and all of this has the potential to really screw up prom night. Which it does. (Hello, "Carrie.")

"Jennifer's Body" is never quite as scary or as funny as it wants to be: Cody's trademark offbeat dialogue ("Where's it at, Monistat?") often feels out of place, and Kusama too often substitutes blood for genuine chills. But Seyfried approaches her role with such honesty and vulnerability that she transforms the movie; you see, in her bottomless blue eyes, that she long ago accepted being the girl that nobody noticed.

By the end of the film, as she races through a dark wood in her awful pink prom dress, she's all that matters. This is Needy's story, not Jennifer's — and she's the reason to see the movie, no matter who's on the posters.

Moira Macdonald: 206-464-27175 or mmacdonald@seattletimes.com