A worthwhile viewing experience that I’d happily repeat and suggest to others. Given its found footage format, set within the French catacombs, the film naturally incorporates shaky camera work and unusual perspectives, creating a genuinely oppressive atmosphere at times. Those who enjoyed "The Descent" will likely find this acceptable as well. The narrative draws inspiration from actual practices—the exploration of historical structures, some forgotten, others abandoned, and still more considered beyond reach for ordinary people. I think it's unfortunate that these locations are treated as illegal sites; I believe individuals should be permitted to improve them as necessary. However, this aspect sets the stage for what unfolds in the film itself. The characters are relentlessly pursued into the catacombs, spiraling further and further into madness. The psychological horror elements are exceptionally well-executed, and the combination of the unsettling mystery surrounding the caves with sudden bursts of violence creates a compelling movie experience. It’s possibly the strongest take on the "philosopher's stone" concept I have encountered.

Source on TMDB