Any film with a Diablo Cody credit following Juno was probably going to take a hit in the press; judging by the cranky Juno backlash, a new film was scarcely even needed. But when Cody’s second produced screenplay turned out to be a high school-set horror comedy starring Megan Fox, the dismissals practically elbowed each other to write themselves: tired genre rehashings! Starring a vacuous starlet! Doing second-rate imitation-Juno dialogue! She—Fox, Cody, the direct of Girlfight, whoever—is so over.

True, at least, that Jennifer’s Body, now on DVD, lacks the emotional payoff of Juno, and that movie’s unexpected charm. But Jennifer’s Body works on its own idiosyncratic terms. As horror, granted, it’s not particularly scary, at least not in a jumpy way—instead, it has an unnerving sense of discomfort in depicting the moment where childhood friends break off from one another.

The friends in question are Anita (Amanda Seyfried), nicknamed Needy, and Jennifer (Megan Fox), no nickname necessary. They’ve been close since their sandbox days, with the crucial distinction that Jennifer must’ve at some point become aware of her hotness while Needy, with her glasses, genial band-nerd boyfriend, and un-bared midriff, remains almost comically oblivious. Residents of semi-backwater Devil’s Kettle, the pair attends a rock show by up-and-coming indie band Low Shoulder. A fire breaks out, and a dazed Jennifer ditches Needy to go off with the band. She returns bloody and bilious, but at school the next day she seems back to her polished hottie self—only maybe slightly more demonic. It’s around then that boys start turning up murdered and half-eaten.

Storywise, Jennifer’s Body proceeds in fits and starts, more a series of vivid scenes and intriguing themes than a propulsive narrative. Instead of showpiece kills, it focuses on Needy’s connection to her friend, established through frequent intercutting between Jennifer’s gothic prowling and Needy’s warmly lit dork life. Their relationship has just the right currents of hostility running through their affection; it takes Needy most of the movie to figure out Jennifer’s evil (“not high school evil”) because at first the evil just plays like an amplified version of Jennifer herself.

Jennifer herself plays like an amplified version of Megan Fox. Fox, with her affectless baby voice and supermodel-dead eyes, is the perfect vessel for Cody’s most ornately dismissive quips and slang. Anyone familiar with Fox’s careless interview style should recognize Jennifer’s talent for bitchy weirdness so assured that it blurs the line between deadpan and ditz, as when she invites a boy (males, in Jennifer/Megan parlance, are always “boys”) over to watch a DVD of forgotten mermaid picture Aquamarine (“about a chick who’s half-sushi”).

Cody’s words don’t sound exactly like “real” teenagers, no, but she understands the way that young, close friends can develop their own slangy language, and stylizes her own version, along with Needy’s tidier, less brazen substitutions—“cheese and fries!” she exclaims at one point, in lieu of anything resembling an epithet. Sometimes those stylizations have a tossed-off showiness, but I can think of worse writerly offenses than having a bitchy teen girl say “move on dot org”, which apparently irritated some critics more than the entirety of Transformers 2. No sooner has Cody established a voice and a style than it’s deemed a creative roadblock— a criticism with the vague implication that female filmmakers should keep to the realm of spare, evocative, mostly humorless indie grit like Frozen River.

In the uneven genre playground of Jennifer’s Body, though, there’s a lot to enjoy: Cody’s sardonic notes on how teenagers react to horrific tragedies; the way the film sometimes treats Jennifer as more of a Tim Burton style sad monster than an easy megabitch; and a fine, empathetic performance from Seyfried, who has proven equally adept at a variety of high school types in Mean Girls, Veronica Mars, and now here.

The DVD release features the theatrical version of the film as well as an extended, unrated cut, presumably trading on the hope of a nakeder Megan Fox or bloodier kills. As is often the case, though, the studio is simply making an alternate cut of the movie sound sexier by not submitting it for a rating; the “unrated” Jennifer’s Body contains, to my eyes, no more sex or violence than the theatrical release.

In fact, the unrated version turns out to be a different kind of geek bait: it’s a director’s cut, though it’s not advertised as such, maybe assuming that the film doesn’t have any fans yet. Maybe this cut will help; it’s not vastly different, but it offers a version of the movie that’s a little more deliberate, a little more strange—many of the additions are as small as extended pauses on a character’s face before cutting to the proverbial chase.

The differences, then, are mostly subtle, and director Karyn Kusama offers a selective commentary on the sequences that were altered for this version, explaining what was changed and what she prefers without sounding bitter over the process. There’s also a second commentary on the theatrical version of the movie where Kusama is joined by Cody.

Oddly, their two-woman track feels less chatty and less detailed. They both highlight strengths of each other’s work and seem respectful of the genre—the way horror can take “an essential emotional truth and amplify it,” as Kusama says—but come off a touch guarded, sometimes referring to inside jokes without explaining them or pausing for short stretches. But maybe the seriousness is appropriate: Cody is often tagged as a snarky, cutesy hipster, but for a mean-girl horror movie, Jennifer’s Body is pretty damned sincere.