Mountain climber Pete Athans' April 2007 expedition to explore human-carved caves in Mustang, a tiny kingdom nestled between Nepal and Tibet, is detailed in a documentary by Liesl Clark, his wife, who also narrates. The team hits a snag in the form of snow, but lucks into a find when a goat herder tips them off to a walk-in cave that holds ancient Tibetan texts and wall paintings.Then, Athans begins the arduous task of accessing caves carved into steep cliffs that hold even more treasures