In this one-night, two-part NOVA special, an intrepid international team of volcano experts climb up to their summits, perilously close to their gigantic craters, to deploy innovative imaging and remote sensing techniques.

The Virunga mountains in the Democratic Republic of Congo are home to two of the most dangerous, spectacular, and least understood volcanoes in the world. In this one-night, two-part NOVA special, an intrepid international team of volcano experts climb up to their summits, perilously close to their gigantic craters, to deploy innovative imaging and remote sensing techniques. They’re seeking clues to the forces at work deep beneath the volcanoes that are splitting East Africa apart, to predict when the next devastating eruptions could occur and to save the lives of large numbers of people who live in the shadow of these monsters.