In 1875, in a small apartment in New York City, a handful of freemasons and spiritualists met in secret. After hours spent debating advances in science and the spiritual mysteries of the Orient, the assembled guests settled on an idea. What the 19th century needed most, they concluded, was an institution dedicated to exploring the untamed borderlands between scientific and religious thought. Two weeks later, the Theosophical Society was born, inspiring a trans-continental occult revival that fundamentally transformed the religious margins of Western society. The movement that followed was an explosive mix of creativity, spiritual longing, and pseudo-scientific mischief. Piggybacking on the idealist zeal of the fin de siècle, major occult sodalities grew like ripples: the Hermetic Order of Golden Dawn, a magical order created by Rev. A. F. A Woodford, William Wynn Westcott and Samuel Mathers; the Anthroposophical Society, created by the Austrian clairvoyant, Rudolf Steiner; and the