This book delves into the ancient Greek Eleusinian Mysteries, a secret religious rite that was held annually for over two millennia. The authors, Carl A. P. Ruck, Albert Hofmann, and R. Gordon Wasson, propose a groundbreaking theory that the Mysteries were centered around a powerful psychoactive substance. They argue that the key to understanding these rites lies in the Kykeon, a sacred drink consumed during the ceremonies. Drawing from a range of disciplines including classics, anthropology, and chemistry, they suggest that the Kykeon was likely a brew made from ergot, a fungus with similar properties to LSD. The authors contend that this psychoactive potion induced profound spiritual experiences in the initiates, leading to transformative insights and personal growth. The book challenges conventional interpretations of ancient Greek religion and offers a fascinating exploration of the intersection between spirituality and psychoactive substances. It is a thought-provoking read for anyone interested in the history of religion, psychedelics, or ancient cultures.