Deep in the jungle of Central Vietnam, lies a magnificent underground kingdom. Hang Son Doong which translates as "mountain river cave", is the largest cave passage in the world and a place of spectacular beauty. With more people having climbed Everest than visited Son Doong, its pristine charm has remained undisturbed for millions of years. In 2014, Son Doong's future was thrown into doubt when plans were announced to build a cable car into the cave. With many arguing that this would destroy its delicate eco-system and the local community divided over the benefits this development would bring, the film follows those caught up in the unfolding events.
A Crack in the Mountain
A small, impoverished Vietnamese community struggles to deal with the opportunity and challenges that arise when Hang Son Doong, the largest cave in the world and a place of extraordinary natural beauty is discovered nearby.