Back in late 2006, when we started seeing people on the El reading novels with a discreet black cover featuring two hands holding an apple, we thought it might be a translated work of serious fiction. Kudos to the genius designer, Gail Doobinin, whose sophisticated covers make the Twilight books safe for adults to read in public. Little did we know that between those covers hid a phenomenon that embodies the cultural enshrinement of mediocre fantasy and train-friendly pop-lit à la Dan Brown.

The novels’ crossing over from the Young Adult ghetto to a much wider popularity was made easier by the increasing cultural acceptance of adults reading kids’ books (thanks, J.K. Rowling). But what does it say about our collective intelligence when the most popular book in America is aimed at teenage girls, and poorly written at that? Certainly, the Twilight phenomenon demonstrates the power of shrewd marketing and online viral culture, but it’s also a symptom of a growing adult fixation with our teen years and, more troubling, a willful retreat into alarmingly outdated gender roles.

It’s easy to understand why young readers love Twilight: Bella’s problems are familiar and uncomplicated (she has sexual longings, but they can’t be consummated, so STDs and birth control aren’t a concern). Teen girls can long for the clarity of her situation while reading all the supernatural stuff as metaphor for the unruly desires of teen boys (sophisticated vampires = college boys; pack-behavior-embracing werewolves = high-school boys). It’s a manageable version of their own social lives, even if its manageability involves a baroque supernatural world of vampires and werewolves.

For adults, the books offer a double dose of nostalgia. Grown-ups can relive the sensation of being young readers—just like they did with Harry Potter and kids’ books and films like Where the Wild Things Are. To settle into the world of Twilight is to forget about job insecurity and mortgages in favor of the old-fashioned gothic-romance problems of the enigmatic suitor and the mysteries of love. It’s key that these aren’t just any gothic romances—most Twilight readers wouldn’t go near Harlequin romances. These are books written for and about teens. Adult readers get to swoon over dreamy Edward as if they were 15 again, which, in our youth-obsessed culture, is much more fun than projecting themselves into conventional romances targeted at (ewww) adults.

Ironically, the adventures of Bella in the Twilight books and films—discovering that there are vampires and werewolves and other evils—resonate for teens as a metaphor for navigating the adult world. For adults, the pleasure comes from pretending to be teen readers puzzling out the very adult world these teens-by-proxy are trying to escape. Weird, huh?

So nostalgia and escape are certainly part of the puzzle, but Twilight’s popularity also speaks to a rear-guard cultural movement, a conservative response to the radical changes in sexual politics of the last decade. Stephenie Meyer has claimed her books are feminist because they are about Bella making a choice, an assertion that would be laughable if so many people weren’t nodding in agreement. The Twilight novels espouse values more suited to 1809 than 2009: They offer up chaste romance with an ideal man, initially mysterious and menacing, who eventually confesses his love for the heroine and protects her from his own unruly desires—and from evil men who want to ravage her (or “suck her blood”). Feminist? Hardly. The Twilight series aims to clean up the sloppy excesses of grrrl-power feminism. It teases readers and viewers with the prospect of burgeoning teen sexuality only to cap it with an abstinence-only message coded through vampirism. As Edward warns, there’s no safe sex when he could lose his precarious control of his urges at any moment. So, one supposes, heavy petting is out, too. How much fun can it be to live as an immortal playboy when you can’t even get to second base?

In the Twilight universe, sexual consummation is blocked by an endless series of obstacles. When Bella first encounters Edward at her new school (why a vampire with two Harvard degrees is hanging around with the Clearasil set retaking calculus is never satisfactorily explained), she misreads his iciness and withdrawal as revulsion. Then she starts to think he might like her but might also be, you know, undead (this is less of an obstacle than you might think for our open-minded heroine). Faced with Edward’s eerie and oft-stressed perfection, Bella falls for him, but the next obstacle is his insatiable bloodlust; every time he gets near Bella, Edward has a craving to drink her dry (which, in the chaste Twilight universe, is an obvious metaphor for raging male hormones). Then Edward and Bella face an external obstacle in the form of another vampire who craves Bella the same way Edward does. In the later books, other vampires come after Bella, and werewolves are thrown in for a little variety.

This combination of teenage sexiness without the actual sex and the sheer number of rabid fans proved irresistible to Hollywood. The film version of Twilight arrived in theaters with a brilliant PR campaign and a strong tailwind provided by the breathy sighs of teenage girls over Robert Pattinson’s calculatedly unruly locks and bedroom eyes. He’s a perfect prefab teen heartthrob, a characterless slab of handsome man-meat with just a hint of wildness (but carefully controlled wildness, of course—hence all the attention to his hair). But the film’s success cannot be blamed on teenage girls alone; adult fans stood in those lines, too.

The second film, The Twilight Saga: New Moon, has been preceded by another shrewdly choreographed saturation-bombing publicity campaign behind Pattinson and Kristen Stewart. And, sensing that Pattinson’s aloof dreaminess wasn’t going to keep the audience fully satisfied, the studio has tapped into a more carnal strain of teen-girl desire, making the oft-shirtless werewolf Jacob Black (Taylor Lautner, already balking in interviews at his objectification) the new It boy of the series.

In the first movie, director Catherine Hardwicke (Thirteen, The Lords of Dogtown) seems most at home dealing with the realistic details of a lonely teenager’s life, and the best scenes in the film involve Stewart’s Bella interacting awkwardly with her father (Billy Burke). But the supernatural aspects are poorly executed. The bizarre blond dye jobs most of the vampire “family” sport are risible, their status as “gods” of the school seems patently ridiculous given what a bunch of weirdos they are, and the scene in which Edward, exposed to sunlight, sparkles like a diamond, is laughable, proving that not all things described on the page can or should be visualized.

Working with typical Hollywood logic, Hardwicke was replaced for New Moon by Chris Weitz, fresh off the Golden Compass debacle. Hey, he did a fantasy film, and he worked with a kid in About a Boy, so he’s the perfect man for a gothic vampire romance! His résumé suggests we’ll get less of the nuance of teen life than Hardwicke delivered and more attention to the fantastical elements. On the other hand, Twilight screenwriter Melissa Rosenberg is back to make sure the film preserves Meyer’s blend of chaste horniness, old-school gender politics and achy pining. Which ought to give teen-envying adults plenty of license to swoon all over again.

New Moon rises November 20.

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