Hoping to catch lightning in a bottle (or the ghost in the machine), Paramount Pictures has been treading carefully with its release of "Paranormal Activity," a pickup from Slamdance 2008 whose ridiculously low budget of $15,000 and cinema-verite approach to the supernatural evoke that ultimate sleeper success, "The Blair Witch Project." The movie's utter lack of production value has mandated an unconventional word-of-mouth strategy that incorporates midnight debut screenings in 13 college towns and a website competition to determine which parts of the country will get it next.

It's a smart move, since much of "Paranormal" is as exciting as the outtakes from a particularly dull episode of "Big Brother." Careful handling is a must for the picture to capitalize on its strength -- an incremental sense of dread that leads to some genuine jolts in the final half-hour. Those shocks should generate an avid cult following, but writer-director Oren Peli's housebound horror tale is unlikely to cast a massive boxoffice spell like the "Blair Witch" phenomenon.

The setup is as elemental as can be. Young middle-class San Diego couple Micah (Micah Sloat) and Katie (Katie Featherston) are being spooked by strange noises in their new home. Eager for answers, Micah decides to set up night-vision camera equipment in their bedroom, in addition to his own roving camcorder. (As in "Blair Witch," all the action is purportedly found footage from this amateur shoot.)

We soon learn that Katie has a history of otherworldly encounters, dating to a tragic incident from her childhood. The couple calls in an ineffectual psychic, and Micah tempts the spirit world with an Ouija board, but their after-dark visitations just get louder and more terrifying, culminating in one particularly momentous night.

The most effective sequences stem from the time-coded bedroom surveillance footage (always speeded up to the moments when doors open by themselves and shadows climb the walls). The banality of the couple's day-to-day existence when they're not hearing unwelcome guests enhances the sense of realism, but it can be awfully trying for viewers who just want to get to the good stuff already.

Sloat and Featherston have a laid-back naturalism that serves the premise well. Sloat is just smug enough that we kind of welcome the hell that awaits him.

"Paranormal" ultimately does deliver in a way that "Blair Witch" never did, but its achingly slow buildup is a test not just of an audience's patience but the power of hype surrounding the latest alternative scary movie.

Opens: Friday, Sept. 25 (Paramount Pictures)
Production: Blumhouse Prods.
Cast: Micah Sloat, Katie Featherston, Mark Fredrichs, Amber Armstrong, Ashley Palmer, Tim Piper, Randy McDowell
Director,screenwriter, director of photography, editor: Oren Peli
Producers: Oren Peli, Jason Blum
Executive producer: Steven Schneider
Rated R, 96 minutes