Volcanologists in Colombia and the Philippines work to answer a question with no easy answer: when will a given volcano actually blow. The film follows scientists monitoring glacier-capped peaks and active craters with seismometers, gas sensors, and satellite imagery, tracking the tremors and sulfur emissions that can signal magma on the move. Field teams hike into danger zones to place instruments directly on unstable slopes, while others analyze decades of eruption data looking for patterns that might give threatened towns enough warning to evacuate. The stakes are concrete: past eruptions in both regions have killed people who had no notice, and the film uses that history to explain why governments now fund permanent monitoring networks. Interviews with the researchers, sometimes called volcano doctors, cover the limits of prediction as much as its successes, including how much uncertainty remains even with modern sensors. Footage moves between control rooms full of readouts and the physically punishing work of getting equipment onto an active crater.