Chris Sharma dangles off the moss-covered rock by two fingers, his feet swaying back and forth as he finds his balance 60 feet above the crashing waves. He finally sets his feet on a slippery nook in the rock below, readying his body to spring. His shining blue eyes are fixed on the target seven feet above him as if it were the only hunk of rock in the world. He jumps and grips the jutting stone for only a second before his chalk-covered fingers slip and he descends back-first into the roiling bay. Sharma swims to the base of the rock, gets a fresh bag of chalk and, without pausing, begins his unfettered ascent for the 10th time that day.

"What makes this climb so hard is that you're hanging from your fingertips the whole time," says Sharma of the rocky arch he is attempting to climb in the middle of a bay in Mallorca, Spain. "On top of that, the wall is absolutely blank for seven feet and you pretty much have to leap to grab it. I must have tried unsuccessfully 100 times before I finally landed it."

The limitless determination of Sharma, a Santa Cruz County resident and "deepwater solo" professional featured in the film King Lines, is hardly a rarity among the athletes featured in the two-day Banff Mountain Film Festival, which will be showing at UCSC Feb. 29-March 1. The avid, even obsessive, outdoorsmen and women profiled in the festival's films pour their passion into just about every extreme sport imaginable--from BASE jumping to extreme downhill skiing to whitewater kayaking to what can only be considered the outer limits of rock climbing. Each athlete is absorbed in his or her own world of extreme physical challenge and torturous internal struggle, yet all are in pursuit of the same goal: the edge of human potential.

Perhaps no extreme sport is more fixated on this goal than BASE jumping, the 30-year-old practice of leaping off cliff faces and high-rise buildings with nothing but a parachute to slow the descent. For Norwegian jumper Karina Hollekim, profiled in the festival's hour-long feature film 20 Seconds of Joy, the edge is never close enough. The film follows Hollekim as she dives off a multitude of cliff faces, each taller, rockier and windier than the last. As the strong-willed thrill-seeker becomes more accomplished and takes ever-greater risks, a realization dawns on the viewer: she will never be completely satisfied with her achievements, no matter how monumental. Over time, Hollekim's harsh childhood is revealed and broader questions of human psychology are raised. What does life mean to those who face death on a regular basis? Is the extreme athlete's control of fear a way to find stability in a chaotic world where control often seems to slip from the fingertips?

The skillful interlacing of these broad-ranging metaphysical questions with an in-depth and complex character sketch helped to make 20 Seconds of Joy the People's Choice award for this year's festival when it was launched in Alberta, Canada, last November.

This is not the only film showcasing the never-ending quest to find the limits of human willpower. 24 Hour Solo, another of the longer films at this year's festival, documents a grueling daylong mountain bike race in Conyers, Ga., through the eyes of six-time world champion Chris Eatough. It's a punishing race that requires each cyclist to stay in the saddle for a full 24 hours, through rocky hills, thin trails that slice through thick brush and the ever-present threat of dehydration and injury. The film draws viewers into the tense, uncertain world of a 24-hour race with such skill that teeth-grinding is nearly unavoidable. The festival isn't all sports psychology and gorgeous nature shots, though. There is also plenty of comedy, most notably in the satirical animation film Badgered, which follows the escapades of a badger trying to get a wink of sleep amid noisy neighbors and destructive human activity.

The festival's films allow viewers a rare glimpse into the quickly evolving world of extreme sports, but always accompanying the new technologies and freshly conquered mountains is the howl of the unknown calling forth the restless.

"Climbing is this ever-evolving thing, and although it is about getting to the top, once you get to the top the experience is finished," says Sharma. "You're constantly looking for new things to climb--there are infinite rocks around the world. It's a never-ending cycle."

BANFF MOUNTAIN FILM FESTIVAL runs Feb 29-March 1, 7pm each night at the Rio Theatre, 1205 Soquel Ave., Santa Cruz. Tickets are $12 students/$14 general/$25 Gold Circle, and are available at Bugaboo, Pacific Edge, Sprockets and the UCSC Recreation office. Visit ucscrecreation.com for full film listings.

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