How did the Catholic Church respond when spirits began to speak through mediums, and occult movements to offer initiation into hidden truths? This book answers that question from inside the Church’s own papers, many of them studied here for the first time. You will find priests exploring trance states to probe the latent powers of the soul, or to recover an esoteric Christianity; séance experiments with a select group of children, encouraged by a pope; and Roman theologians who read paranormal phenomena as proof that the devil was at work. What emerges is a Church that studied what it feared, and in condemning it helped define its religious Other. At stake was never doctrine alone, but religious experience itself: who could reach the invisible, and how?