If you haven't noticed the vampire stalking your TV, your YouTube account, the local bookstore, and probably the high school down the street—you're about to. Edward Cullen has left a mark on teen girls' hearts, and he's sure to leave more after his debut in theaters this weekend.

The teenage vampire, or rather, the actor who plays him in the film adaptation, Robert Pattinson, has become the new media darling. Entertainment Weekly plasters him on the cover every chance they get, Vanity Fair and In Style have him dolled up in their current issues, and Perez Hilton tracks his every move. Little Brown's Twilight, the book that started the phenomenon, has trouble remaining on bookstore shelves. And young girls all over America have lost sleep in the past few weeks—not by staying up late into the night watching movie trailers or reading the final installment of author Stephenie Meyer's four-book saga, but by literally camping out at malls long before dawn breaks, waiting to catch a glimpse of their beloved "Edward" as the actor finishes up his 12-city media tour. Additional sleep was lost last night, when midnight screenings of Twilight sold out 80 percent of shows.

These girls, and not infrequently, their moms, have been breathlessly awaiting the arrival of Edward to the big screen ever since the character told his fictional love, 17-year-old mortal Bella Swan, that he was "tired of trying to stay away from her" in Meyer's 2005 novel of the same name. "Team Edward," as Cullen fans call themselves, is ready.

But what about everyone else?

Twilight may mark the end of obscurity for almost everybody involved in the journey from underground hit three years ago to feverishly awaited adaptation, which arrived at 12:01 this morning. Summit Entertainment, the small L.A.-based studio that scooped up the movie rights after Paramount passed, has never had a sure-to-be-hit like this on its hands before. Author Stephenie Meyer was a stay-at-home mom before she dreamed up the vamps. Kristen Stewart, who plays Bella, has repeatedly told the press she believed she was signing on to do a small indie, her usual fare.

Tina Wells, C.E.O. of Buzz Marketing, a group that specializes in the teen demographic, says she can't remember another instance where the already-established audience seemed a little more attuned to a movie's potential success than the people behind it. "I honestly can't. I can think of several situations where the producers thought a film was going to be huge and it was a complete dud, though." But, "I think that no one was really prepared for how big a phenomenon Twilight would be." It seems a strange oversight by the production company and the cast, considering the book series has steadily grown in popularity. Last summer, Twilight's second sequel, Eclipse, dethroned the final Harry Potter book upon its publication only three weeks later.

Summit, whose last film, Sex Drive, grossed only $8.3 million at the box office, may itself be fueling the low expectations. Last month, the studio said it expected to earn $20 million at the box office, and only increased that number to $30 million when tickets sold out in many theatres, forcing major chains like AMC to up the weekend's showings from approximately six a day to close to 20 in metropolitan areas. Those figures still fall far short of the $60 million analysts such as Wells, well aware of the movie's buzz among high schoolers, are expecting. 

Robert Bucksbaum, president of Exhibitor Relations in Los Angeles, agrees that Summit is definitely aiming low. "We're saying $55 million," for the total, he reveals, adding that he believes Friday alone will bring in $25 million for the movie.

The gravity and reach of the series is slowly dawning on its stars. On-camera interviews with Stewart and Pattinson (mostly known for a small role in the fourth Harry Potter movie) show them having trouble articulating the mania surrounding Twilight. "Wow, this must've been what it felt like to have a medieval battle…I don't know, it's really strange," Pattinson told EW.com regarding close encounters with his fans. The New York Times reported a similar impression of Summit's leaders, saying, "the studio's executives seem a bit discombobulated by all the fuss…and they had trouble explaining the brand."

Bucksbaum says the studio's hesitance is likely a combination of inexperience and caution. "[The studio] is not a Disney or a Warner Bros. We're talking about Summit. If they claim they're going to make $60 million and they only make $50 million, everyone will be disappointed. I mean, $10 million is huge for these guys."

Plus, adds Wells, "The book was a major blockbuster, but you just never know how things will translate across platforms."

But the Twilight fans who've already reserved tickets aren't confused at all. And regardless of how the cast members and execs at Summit feel, it seems like this could be it: Twilight is falling on their low profiles.

"It's a one-in-a-million shot for a small studio to come upon a movie like this," Bucksbaum claims. "They didn't spend a lot of money on location, on actors—and now they've got a franchise."

Says Wells: "The fans are incredibly committed to this brand, and if the recent mall tour is any indicator"—that would be the medieval warriors Pattinson speaks of—"this is going to be a huge hit."