The Andes is the longest mountain range in the world and home to astonishing hidden worlds, extraordinary animals and remarkable people. A female puma and her three cubs hunt in the mountains of the frozen south. Spectacled bears search for water on scorched mountain forests and the descendants of the Inca gather in an ancient ceremony to build a bridge made from woven grass. High in the cloud forest, the newly discovered shape-shifting frog baffles scientists with its superpowers and in the Atacama desert - the driest place in the world - strange reptiles battle for access to precious water. This is the mountain range of surprise and wonder.