Robert Kenner’s new documentary FOOD, Inc. opens with a shot of a glowing cornfield and a quaint red farmhouse. Within minutes, headless chicken corpses the color of a sidewalk fill the screen, rolling down a factory assembly line. Shock value is the point here: The film, in wide release this month, is a wake-up-and-smell-the-pesticides primer on big agriculture, covering everything from E. colitainted cattle farms to how companies like Monsanto force out local growers with patented, genetically engineered seeds. These issues are old news to anyone who has read The Omnivore’s Dilemma or Fast Food Nation, whose authors, Michael Pollan and Eric Schlosser, provide narration (a bit too much at times). But FOOD, Inc. may be just what the local-food movement needs right now: Like another big-screen exposé, it’s not so much a groundbreaking work of reporting as a vehicle for communicating an inconvenient truth that’s shocking in its simplicity. After all, before Al Gore turned melting glaciers into Hollywood’s cause célèbre, many considered climate change a fringe issue.