Anxious times demand scary movies. Just as postwar Japan worked through its nightmares with "Godzilla," "Rodan" and other behemoth-as-bomb horrors, post-9/11 Hollywood has churned out apocalyptic epics that compress our worries about alien threats into monster melodramas that can be resolved in the time it takes to eat a box of Raisinettes.

"Cloverfield," the hush-hush creature feature from "Lost" producer J.J. Abrams, gives the genre's classic themes an audacious spin -- and wobble and quiver and tremble and shake. It's the end of the world as captured on an unsteady camcorder, a YouTube panic attack.

The premise is inspired. The events of the story are presented as a recording salvaged by the Department of Defense from the area formerly known as Central Park. It begins innocently enough, with an attractive young couple, Rob and Beth, waking up after a night of sheet-rumpling passion, flirting with one another on camera, and planning a day trip to Coney Island.

Those images are interrupted by footage of Rob's going-away party, date-stamped three weeks later. Rob's pal Hud is assigned to document the boozy party, and we meet a handful of the crowd wishing him sayonara and good luck in Japan. Beth appears, clashes with Rob and leaves in a huff, putting a pall on what one partygoer tells the camera is "the best night ever." Then something shakes the ground with earthquake force, explosions light the skyline and the evening takes a swift turn for the worse. Hud never stops filming because "people will want to see how this went down."

"Cloverfield" uses its caught-on-video framework effectively, giving the fanciful story a texture of authenticity. It strips away the baggage that encumbers most big-canvas monster movies. The focus is tight and sharp. There's no precocious blond kid to be rescued, no vain comic-relief anchorman on the TV, no scientists offering logical explanations, no faithful dog for the hero to confide his worries to. There's hardly a hero, just Rob and a couple friends running away from "something terrible" in ingeniously realized disaster footage.

The streamlined story plays out in a swift 80 minutes. We see only what Hud's camera sees: distant devastation, flashes of a gargantuan monster, anonymous soldiers fighting back and endless creepy subway scenes as Rob and company sprint underground from SoHo to Midtown Manhattan in search of Beth. Like a hazy memory of better days, snippets of the Coney Island excursion blip in and out of the current-time catastrophe footage.

The video-verité approach is clever, but the raw immediacy comes at a steep cost. The incessantly shaking camera made several viewers at the screening I attended complain of nausea. The deliberately amateurish look of ominous underexposure, blinding overexposure and washed-out color will have many itching to adjust the screen settings.

And the doggedly realistic tone of the piece means there's precious little fun to be had here. After the good-natured bustle of the party scenes and a moment of levity about "Cloverfield's" top-secret production ("I hope this doesn't wind up on the Internet," Beth says as Rob captures their first sleepover on video), it's sturm und drang nonstop. The tension is flawlessly maintained, but the problem with one-note films is that eventually that note goes flat.

More damagingly, the third act is cluttered with false endings that give the climax a stuttering conclusion. The actual finish, when it finally arrives, echoes the now-fashionable gloom of many doomsday dramas, as if the creativity that sent the project roaring off the starting line was depleted. It's frustrating to find the proper grace note to wrap up one individual's story; end-of-civilization yarns are a million times harder.

Colin Covert • 612-673-7186