Beneath our feet lies a hidden world of profound mystery and ancient history. Guided by the narration of Sandra Hüller, this captivating documentary from director Rob Petit descends into the planet's most extraordinary subterranean realms. The film explores deep time through the lens of caves, catacombs, and otherworldly landscapes carved by nature and human hands, revealing stories of life, death, and the very essence of our existence. As the journey unfolds, viewers are confronted with the delicate balance between humanity's quest for knowledge and the imperative to preserve these fragile, dark ecosystems. With a haunting and meditative atmosphere, Underland becomes a breathtaking cinematic expedition that challenges our perception of the world above by illuminating the profound secrets buried below.