America may be in love with vampires once again.

Hype for "Twilight" is building up to a crescendo as the movie opens in theaters nationwide today. British actor Robert Pattinson is the star of the show, a tale of a vampire who befriends a mortal woman who falls in love with him. The 22-year-old Pattinson is known in Harry Potter fan circles as Cedric Diggory, a character in the last two Potter films.

The movie is based on the book "Twilight," the first of a four-book series on vampires by author Stephenie Meyer.

Excited fans have filled malls and bookstores across the country before the movie premiere. Officials at Orland Square mall in Orland Park, Ill., estimated close to 3,000 fans of the actor and the books filled pavilions last week inside the mall. Pattinson visited the mall as part of a cross-country, Hot Topic-sponsored press tour. Five hundred attendees got autographed posters while others enjoyed Pattinson as he answered questions about himself, the movie and his heartthrob status.

One week ago, the Borders store in Highland had a party celebrating all things "Twilight" and Pattinson. Event coordinator Theresa Hohos said at least 40 girls showed up to do activities, discuss the casting choices for the movie, listen to the movie's soundtrack and play charades using characters from the books.

"It went really well, but it was not as busy as the book release," Hohos said. She said at least 400 people attended the midnight book release of Meyer's fourth book "Breaking Dawn." She said the girls chided her for only reading "Twilight" out of the series. Hohos said she enjoyed it, but she still is surprised at how popular the franchise is now.

"I cannot believe how huge this book is," Hohos said. "This kind of came out of nowhere."

Schaumburg resident Bill Anderson went to the Orland Park event and said "Twilight" has captured imaginations because the vampires don't have fangs and can be present in the daylight, which are traits not in typical vampire flicks. Anderson, 16, thanks his sister Kristen for getting him into the books and said he read the four books in a two-week period.

"I'm a huge Harry Potter fan, but this is slowly taking over that spot," Anderson said.

Purdue University communications professor Glenn Sparks said "Twilight" has the potential to alter people's attitudes on whether vampires exist and other paranormal phenomenon. Sparks has published studies on the effects of supernatural television shows.

"Research on paranormal beliefs shows that when a fictional story is successfully presented in a realistic way, it can move people to believe or at least move them away from disbelief and toward more uncertainty about the supernatural," Sparks said in news release.

The movie is rated PG-13.