Grade: 3.0/5.0

“Fire of Love” — a documentary about maverick Alsatian volcanologists Maurice and Katia Krafft, who died horrifically and predictably in the eruption of Japan’s Mount Unzen in 1991 — is worth seeing for what it does not do.

Despite the mawkish title — and despite the even more mawkish Rolling Stone quote on the poster declaring that Sara Dosa’s documentary is “The greatest lava-fueled love story ever told” — the Kraffts never touch in the movie. In fact, they’re barely within grasp of each other unless tag-teaming a volcano lecture on a talk show.

The film only gains from this because it shows extraordinarily well that the Kraffts didn’t need to touch or talk to consummate their love. The couple really was crazy about volcanoes; it was enough to touch them, to talk about them. In Generation-Z-speak, these sulfuric spewers were their love language.

It is embarassing but undeniable that the only erotic things about the film are the volcanoes themselves; it doesn’t help that much footage of the stretching, throbbing, folding and spewing masses is set to French lounge music. Lava was practically made for the camera. No words or stills could capture the alternate parched black rockscapes and roiling, seething slag, and the editing here is superb (though it’s not a job one could really botch). 

This film was made for the faint of heart. There are unforgivably twee cardboard-cutout animations. There are criminally cliched lines (inexplicably narrated by Miranda July) about the Kraffts’ undying love for some simmering vent that make one wonder what’s taking the leaky lump so long. What renders the film inferior to the other great volcanologist documentary of this century, Werner Herzog’s “Into the Inferno,” is the fact that Dosa only hints at why the audience should care. Herzog’s film gets so close to the fire that it’s humanized, revealing the fear and fury associated with eruptions to be a construct of the cultures that suffer them.

By contrast, Dosa’s film gets so close to the fire that the very bounds of humanity are melted. This is not the clock time of daily life but the geologic time of centurylong creep and secondslong chaos. Before the human experience of this destruction, scientific hairsplitting feels insidious and mythic form apt: Vesuvius, Tambora and Pele are “the devil’s cauldron” or “a bathtub with a hole in it, sowing death all around.” 

To be sure, this is one of the year’s most interesting documentaries. Like so few of them, it ends too soon. The can’t-believe-it’s-not-CGI magma visuals alone guarantee that no viewer will feel shortchanged. To the illimitable benefit of their audience, the Kraffts exhaustively filmed every trip — the blasts were too quick for observation at the moment, and they needed the lecture tour money to keep trekking. 

Nevertheless, the film just falls short on a higher level. It would have been fascinating if the writers presented the Kraffts’ love of fire in terms less hackneyed than “flirt(ing) with death” and “living at the edge of the abyss.” The love story, however explosive, fails to rise above cliche. A documentary can’t afford to do this the way that gloriously formulaic volcano-disaster thrillers such as “Dante’s Peak” and “Volcano” can. 

“Fire of Love” destroys as it creates. As it ends with the volcanologists’ own destruction, it questions their purpose before the agents of destruction themselves. Maurice says, “It’s my dream that volcanoes no longer kill.” If only the motivation behind this dream and the emotions behind its failure were probed as critically as the volcanoes themselves.

Natural disasters in the 21st century are owed not to ignorance but neglect. For those who neglect safety in the name of studying these disasters, “curiosity is stronger than fear.” Pyroclastic flow impressions on Mount Unzen show that the Kraffts were touching as they perished. The hands on Maurice’s watch are frozen to that moment. 

Yet, the couple who died taking the Earth’s pulse knew that the only impossibility is permanence. If they — and those watching them — leave anything that lasts, it is the stories they tell about the phenomena they see. At one point, Maurice asks: “When you can die at any moment, what do you leave behind?” This film does not even leave itself.