THERE'S A MOMENT in Elements: A Slacklining Adventure when one of the athletes walking on a high wire across a deadly beautiful gap in the Alps is exactly on the cusp of losing it. Obeying some sick law of physics, the slackline has transferred the energy of quaking legs into an alarmingly extreme elliptical pattern, and the guy is riding it out on the razor's edge of complicity and helplessness. And suddenly the appeal of this sport, which seems so wrong at first, is clear. It's about reaching your goal by going with the flow, accepting reality and not getting bucked off. It's a meditation.

That's it for the deep stuff, class. The rest of the films in the Radical Reels Film Tour, a project of the Banff Mountain Film Festival, are pretty much pure mainline adrenaline delivery. Canadian pretty boys in swim trunks and tattoos hurl themselves sideways off cliffs into waterfalls and rock-strewn pools 100 feet below. Free-ride mountain bikers sail an impossible distance into the air, do a front flip, land hard and keep going. BASE jumpers wearing odd doll-like suits launch off alpine cliffs and graze hillsides, then wax poetic about defying death. Climber Steph Davis undertakes a truly death-defying solo free-climb up the nasty vertical (or overhanging) face of the Diamond in Rocky Mountain National Park.

But snow is king. This year's Radical Reels has a special place in its heart for extreme forms of snowboarding. In one film a quartet of madmen fly through a village on their boards, grinding rails, rooftops and everything else to a classic thrasher soundtrack. In another, snowboarder Ueli Kestenholz and paraglider Mathias Roten, both wearing paragliding rigs, free-ride the most unforgiving mountain faces Alaska can supply, soaring over cliff edges to the near-vertical slopes below, two specks in an immense landscape of ice and black crags. Still another film shows a gang of feral snowkiters wreaking havoc on the powder of Norway, the Alps and North America, like characters from a remake of Mad Max set in a new Ice Age.

It's hard to sit still through a Radical Reels Film Tour. But then again, that's the idea.

RADICAL REELS screens Saturday, Sept. 26, at 7pm at the UCSC Media Theater, UCSC. Tickets $12 general/$10 student. Proceeds benefit the UCSC athletics and recreation departments.

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