Two expeditions into the Democratic Republic of Congo's volcanic heartland, led by volcano expert Chris Horsley. The first follows Mount Nyiragongo's eruption, which sent lava into the city of Goma, killed thirty-three people, and destroyed nearly four thousand homes. Horsley and his team push through rebel-held jungle to the crater rim, then abseil into the volcano itself to install a live-stream camera meant to give Goma's quarter of a million residents advance warning of the next eruption. The second half returns to the Congo to investigate Mazuku, or 'Evil Wind,' a gas phenomenon killing livestock along a ten-mile fracture near Nyamuragira Volcano. A UN helicopter flies the team in under cloud cover to dodge ground-to-air missiles, dropping them into the crater itself, where Horsley has one hour to gather data through acid gas clouds before the mission has to end. Knife-edge summits, collapsing crater walls, and rebel territory frame both expeditions.