Photographer Stephen Alvarez captures the intricate underground world of Paris, including catacombs that house millions of bodies and hidden tunnels frequented by 'cataphiles'—explorers who engage in various activities from partying to painting. The document explores the contrast between legally accessible sites like the catacombs and illegal exploration of forgotten tunnels, highlighting the vibrant culture and art created by those who venture underground. It emphasizes the community's spirit and the unique experiences of nighttime festivities in this subterranean realm.