Boulder mountaineer Cory Richards has climbed some of the world’s highest, toughest peaks, often filming his trips. But his skill and experience didn't stop him from worrying, earlier this year, as he got ready to climb a 26,000 foot peak in Pakistan called Gasherbrum II.

"I'm scared," Richards says in "Cold," his recent documentary about the climb. "So many things here trying to kill me."

“Cold”  is lighting up the festival circuit. It just won grand prize at the prestigious Banff Mountain Film Festival. Audiences get to see Richards become the first American to summit an 8,000 meter peak in the dead of winter. They also experience the avalanche that nearly killed him on the way down.