SAN FRANCISCO - It's late Friday night outside the arthouse Roxie Theater, and a line is forming down the block. Twentysomethings - mostly men - stand around joking and waiting to file in. The smell of pot permeates the cold, damp air.
Underneath the theater's marquee, a fast-talking Vietnamese man in a suit and tie dashes around with a camera crew in tow, hastily laying a makeshift red carpet on the sidewalk and directing people to stand, pose, smile.
He is James Nguyen, a writer and director, and his movie, "Birdemic: Shock and Terror," is about to make its San Francisco premiere. A former Silicon Valley software salesman with no film-school education, Nguyen made this homage to his idol, Alfred Hitchcock, for about $10,000.
He set and shot his killer-bird saga in nearby Half Moon Bay and Santa Clara, and after showing it to sold-out crowds across the country, this is his homecoming.
Lots of people make bad horror movies. Yet "Birdemic" has become an instant cult classic, one of several such movies that has gained popularity online and through social networking sites. It's got the kind of beloved status that used to take years or even decades to achieve through video rentals and late-night cable.
The schlockery of "Birdemic" is evident from its trailer, which has hundreds of thousands of YouTube views: uncomfortable dialogue, stiff acting, shoddy lighting, jumpy edits. And then there are the eagles and vultures that terrorize a quiet town before bursting into flames. To describe them as cheesy would be charitable. Characters swat at them with wire hangers, which have become the film's trademark.
First in line in San Francisco, Korrena Bailey said she heard about it from a friend back home in Ireland who's a B-movie aficionado.
"The birds explode! There's no better reason (to see it)," she said, smiling. "The special effects are obviously top-notch."
Still, Nguyen insists fans are drawn to its sincerity, and not just coming to cackle. His film has screened for executives on the Paramount Pictures lot, and he's working on a sequel, "Birdemic: The Resurrection."
"It's a good story, there's some humor to it, and people like that," he said. "Despite all of its imperfections - from the visual effects, the animation, you name it - the audience will acknowledge that and see through that."
Laughing at the earnestness and ineptitude of such movies is only part of the allure; doing it in a theater packed with people is the bigger draw, said Michael Paul Stephenson, star of the 1990 cult favorite "Troll 2."
"These films celebrate the communal experience of watching a film together. That's something that's passing away," Stephenson said.
When Evan Husney of Severin Films saw "Birdemic" at the Sundance Film Festival in 2009 - where it had been rejected, but Nguyen brought it anyway - he had no idea what to make of the movie.
"A lot of things were just astonishingly wrong with the film in terms of the audio. I think the cut of the movie we saw was even worse," Husney said. "The first 20 minutes of this thing, I wasn't convinced it was real until it started to sink in: There is no way that a film like this could be faked."
Still, Severin picked it up, and sites such as Twitter - with help from celebrity fans - have propelled it.
"Rainn Wilson has 1.9 million followers," Husney said. "That's an instantaneous blast e-mail to 1.9 million people who are into this guy and are going to want to see what he recommends."
Social networks also have created buzz for a horror movie with far better production values, "The Human Centipede," which has played at packed midnight shows in New York and is expanding this month.
How to describe it tastefully? A mad German scientist abducts people for an experiment in which he attaches their bodies to each other to make, um, a human centipede.
IFC Entertainment president Jonathan Sehring said he knew something was up when his company acquired the movie at Fantastic Fest last year, and the plot description alone got people tweeting. Among the earliest to write about "The Human Centipede" on Twitter was actor-director Kevin Smith, who has nearly 1.7 million followers.
"In a really fragmented audience, with a world of choices and options as to how to spend your time and your entertainment dollar, to get people you trust saying, 'See this film, oh it's great,' you can't buy that," Sehring said.
Messages on MySpace helped Stephenson realize the cult popularity of "Troll 2," about a family that's attacked by goblins, and rated the worst movie ever on IMDb.com.
Now, "Troll 2" plays to sold-out screenings, where fans mob the actors for photos and autographs, and Stephenson has made a documentary about its unexpected popularity, "Best Worst Movie."
"They'd start sending me pictures of 'Troll 2' parties they were having in their basements," Stephenson said. "I remember looking at the pictures and seeing the genuine fun and enjoyment they were having with the movie, and thinking, 'Why?'"
But the mother of all recent cult movies - which was made in a deadly serious way but has produced midnight belly laughs for seven years - is "The Room."
For the uninitiated, "The Room" is a love triangle between Johnny (writer-director-producer Tommy Wiseau), his fiancee and his best friend. It has all the wooden acting, chintzy production design, tacky melodrama and choppy edits you might expect. But any movie can be bad. "The Room" is surreal.
Fans flock to screenings with plastic spoons, which they hurl at the screen in a bit of "Rocky Horror Picture Show"-style interaction. Recently, "The Room" sold out New York's historic, 1,200-seat Ziegfeld Theatre; Wiseau's next goal is to show it at Staples Center in Los Angeles.
Nearly 10,000 people "like" it on Facebook, and there are countless tributes and mash-ups on YouTube. But Wiseau insists social networks haven't made it a worldwide hit: word-of-mouth has, and the power of its symbolism.
"'The Room' connects people," he said. "I think very strongly 'The Room' eliminates crime in America. Young people, imagine what they do before midnight? People always do crazy stuff. If you go see 'The Room,' you have a groovy time, you interact."
So, if audiences are laughing at his movie?
"This is, for me, irrelevant," Wiseau said. "I would not change anything with 'The Room.'"
And neither would its fans.