Set in late summer 1999, Malevil depicts a world transformed by a sudden nuclear cataclysm. The story focuses on a group of survivors in rural France who happen to be meeting in the deep wine cellar of a medieval château when the blast occurs. They emerge to find a "scorched world" where the landscape has been stripped of vegetation and modern infrastructure has vanished, leaving them in an isolated, primitive state of existence.

The societal dynamics shift toward a neo-medieval structure, where the fortified castle becomes the center of a new micro-civilization. Unlike many grit-focused apocalyptic films, Malevil emphasizes the restoration of agrarian life and simplified social hierarchies. Earth is portrayed as a fragmented collection of feudal pockets where survival depends on control over land and food. A significant divergence from typical Cold War tropes is the "clean" nature of the explosion—implied to be a lithium bomb in the source material—which allows for immediate agricultural activity without the immediate decay of radiation sickness, though the film maintains a dazed, surreal atmosphere.

The film’s predictions center on the fragility of modern connectivity and the rapid reversion to localized, authoritarian leadership. While the 1999 of reality was defined by the rise of the internet and globalism, the film's 1999 predicts a total collapse of the digital and telephonic age, returning humanity to a state where "the radio simply cuts out" and never returns. The ending provides a cynical comparison to real-world disaster management; whereas the novel suggests a long-term rebuilding of society, the film introduces government remnant helicopters that represent a forced, potentially unwelcome reintegration into a surviving military-industrial state, suggesting that even after the end, the old world's power structures never truly died. Analysis-quality sources specifically discussing 1999 technological predictions are limited, as the film focuses more on sociological and pastoral outcomes than hardware.