Twilight: The Fangirls Cometh, with Cash

One dark, rainy night last spring, a young woman brought an offering to the rural Oregon movie set of Twilight. "She gave her infant to a vampire," director Catherine Hardwicke marvels. Actually, the Twilighter — as the mostly female devotees of Stephenie Meyer's vampire romances call themselves — had driven hours to get pictures of her baby with the cast. Even before Twilight hits theaters Nov. 21, the series' readers have exhibited enough excitement — if not hysteria — to persuade the studio, Summit Entertainment, to get screenwriter Melissa Rosenberg cracking on adaptations of the next two books. (Read TIME's 10 Questions with Stephenie Meyer.)

Twilight is just one of a wave of movies challenging the conventional wisdom that the taste of young men is what drives the box office. This year female fans helped make monster hits of High School Musical 3 ($84 million), Mamma Mia! ($144 million) and Sex and the City ($152 million). "[Female-centric films] used to be counterprogramming to something extremely male in the marketplace," says Chuck Viane, Disney's president of distribution. "Now they've become the gorilla in the marketplace." (Read Richard Corliss's review of Twilight.)

As they learned to do with their macho comic-book movies, studios making films from more female-skewing properties have begun assiduously courting the alpha fans, the diehards who get the buzz started through their blogs and podcasts. "From the beginning, we were very focused on signaling to the fan base that this film would be everything they wanted," says Summit CEO Rob Friedman. That meant keeping Meyer involved in script and casting decisions as a custodian of her original girl-meets-vampire vision. Early on, for instance, the author put her foot down to preserve certain details that were important to her — that in her stories, for instance, vampires have no fangs and their skin sparkles in the sunlight.

Summit stoked the anticipation by doling out trailers, photos and sound-track news to hungry fans via websites like Twilighters.org, BellaAndEdward.com and TwilightMoms.com. In July, the studio brought the cast to Comic-Con in San Diego, where, for once, shrieking fangirls outdid hooting fanboys in the audience — in number, ardor and decibel level. In recent weeks, the studio sent Twilight's 22-year-old British star Robert Pattinson on a tour of appearances at the mall-based clothing store Hot Topic, where he was greeted by Beatlemania-caliber crowds. Pattinson's San Francisco appearance was canceled after a crush of fans left one girl with a broken nose.

Along the way, the escalating fervor of the Twilight audience — a group that bought 17 million books — helped Hardwicke make the movie she wanted to make. "I used that as a tool to convince the studio to give me more money," the director says. "I said, 'Let's do it right for the fans.' " (See 90 years of vampires onscreen.)

If early ticket sales are any indication, surrendering to the Twi-hards is working. Twenty-four hours before the film opened, some 2,000 shows were already sold out, many of them midnight Thursday-night screenings. And in a survey Fandango conducted of early ticket buyers, 85% said they plan to see Twilight more than once. It wouldn't be the first time young women paid to see a movie over and over again; the same demographic helped Titanic become the highest-grossing film of all time.

It's not just young women clearing their calendars this weekend, either. Half of the respondents to another Fandango survey of Twilight ticket buyers are over 25, including many Twilight moms. About a quarter of respondents are mothers and daughters planning to see the movie together.

Twilight seems sure to mint a new femme franchise. But to become Hollywood's holy grail — a movie that studios consider a "four-quadrant" hit, appealing to young and old, male and female — it will need to reel in some Y chromosomes. Iron Man, for instance, won over mostly male comic-book fans first but rode their approval to an opening-weekend audience that was more evenly split by gender.

Hardwicke says she was told by the studio not to worry about appealing to guys — with a production budget of only $37 million, Twilight will be profitable with or without them. But men who are dragged by their ears to see this movie may be surprised; besides the romance, there's a trio of bad vamps who wreak havoc, and a fast-moving game of vampire baseball. "The teenage girls are the early adapters, but that doesn't mean the train will stop," says Hardwicke. "Besides, young guys are smart enough to go where there are a lot of hot young girls." After all, a love affair with a fictional vampire will have to end someday.

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