In “Fire of Love,” the voice-over quotes Maurice and Katia Krafft’s feelings about the risks in their line of work: exploring and filming volcanoes. “I prefer an intense and short life to a monotonous, long one,” Maurice wrote. Katia acknowledged the danger but said that in the moment, she didn’t care at all.
The Kraffts, married French volcanologists, were killed June 3, 1991, observing an eruption of Mount Unzen in Japan. But the stunning 16-millimeter footage they shot throughout their careers — full of gushing lava, flying rocks and giant clouds of smoke — lives on in the new “Fire of Love,” an all-archival documentary compiled from roughly 200 hours of their material along with 50 hours of TV appearances and other clips.