Professional snowboarder Ralph Backstrom and skiers Hadley Hammer and Sam Anthamatten set out to tackle the fabled Corrugated spine lines of the Tsirku Glacier. Confronted with both anxiety and incitement the athletes are on a tightrope walk between taking only as much risk as needed and failure. Located deep in the Saint Elias mountains where Alaska, British Columbia, and the Yukon converge, this is a place most skiers and snowboarders only dream of visiting.