Drawing from fifteen years of research, classicist and lawyer Brian Muraresku reopens the investigation into whether the earliest Christians and ancient Greeks shared a secret sacramental technology — an entheogenic Eucharist capable of producing direct experiences of immortality. Building on the work of R. Gordon Wasson, Albert Hofmann, and Carl A.P. Ruck in The Road to Eleusis, Muraresku travels from the ruins of Eleusis to the catacombs of the Vatican, uncovering traces of a pre-Christian mystery religion centered on the Divine Feminine and ecstatic communion through psychoactive wine. The book bridges science, theology, and ancient spirituality, suggesting that the “lost sacrament” of the West may have been hiding in plain sight.