The title of Ben Coccio's disquieting debut feature Zero Day refers to the fateful morning when two teenage boys intend to carry out a Columbine-style massacre at their Connecticut high school. Rather than set a specific date like Eric Harris, Dylan Klebold, and all the others who blazed the trail before them, they ready themselves for action and agree to strike on a day when the radio weatherman predicts a temperature of zero degrees. But as the film progresses, the "zero" in the title resonates in other, more unsettling ways, coolly detailing an event that offers no apparent purpose or tidy explanations. Much like Lionel Shriver's recent novel We Need To Talk About Kevin and Gus Van Sant's upcoming Elephant, Zero Day reacts against the politicization of school shootings like Columbine, which gave finger-pointers from all sides a facile "cause" through which they can advance their own agendas. Coccio doesn't have any answers, but he's dissatisfied with the ones that have been coughed up, and his self-conscious killers share his revulsion. With camcorder in hand, Calvin Robertson and Andre Keuck record their meticulous planning period for posterity, partly for kicks but mainly to make certain their awful legacy isn't chalked up to neglectful parents, violent video games, or gun-show loopholes. Though comparisons to The Blair Witch Project are inevitable, the impeccable first-person camera technique not only makes sense dramatically, but also facilitates a complex and queasily ambiguous relationship between the conspirators and the audience. Like many in the reality-TV generation, Robertson and Keuck seem born ready for their 15 minutes, and they treat the camera like an old friend, shrewdly calculating their diaries and confessions for maximum spin control. Stored for future scrutiny in a safe deposit box, the tapes are remarkable for their ordinariness: Once the would-be killers leave their private world of pipe bombs and semi-automatics, they reveal no signs of psychosis. They interact smoothly with their folks (nicely played by Robertson and Keuck's real-life parents) and keep a low profile among their classmates. One of them even takes a girl to the prom, though Coccio drops vague hints about the conspirators' repressed homosexuality. As Zero Day creeps toward a disturbing catharsis, the "found footage" seems less like a gimmick and more like a window directly into its characters' souls, as startlingly realistic as Blair Witch but divorced from any genre trappings. For conceptual reasons, if nothing else, Coccio errs by not leaving the rampage itself to the imagination. (Although in light of the horrific surveillance footage shown in Bowling For Columbine, his no-budget approximation is uncanny.) Yet contrived as they are, the fictions of Zero Day still seem more plausible than the stories offered up about Harris and Klebold, who changed from individuals to symbols within the space of a news cycle.