The Order of the Solar Temple loses 53 members to violent deaths in Switzerland and Canada in October 1994, an event Swiss police call mass suicide but which many observers doubt from the start. A year later, 16 more members die on an isolated plateau in France. The film builds its account around Thierry Huguenin, the only survivor of the Canadian deaths, whose interviews describe a secretive, strictly hierarchical group blending Christianity, New Age belief, and secret-society ritual, one that demanded members surrender their possessions and prepare for an apocalypse their own deaths were meant to trigger. Investigators and journalists lay out what evidence exists and what does not, including the group's ties to far-right politics through links to France's National Front. No one has ever been tried for the deaths, and the film treats that fact as the case's unresolved center rather than a footnote, leaving the murder-or-suicide question open at the end.