The ancient ritual drink used in religious ceremonies and known as soma in India and as haoma in the Zoroastrian tradition is praised in the highest terms - as a kind of deity - in both Zoroastrian and Vedic texts, which date from around 1,700 - 1,500 BCE. It is said to provide health, power, wisdom and even immortality. Many theories have been published about the possible botanical identity of this 'nectar of immortality', a plant which appears to have psychedelic/entheogenic properties.Matthew Clark spent several years researching and travelling widely in his quest of soma. In his fascinating, original and highly readable book, this modern explorer of ancient wisdom reviews scholarly research, explores mythology and ritual and shares his extensive knowledge of psychoactive plants and fungi. The author suggests that the visionary soma drink was based on analogues of ayahuasca, using a variety of plants, some of which can now be identified.Dr. Matthew Clark is a Research Associate at the School of Oriental and African Studies (University of London), where he has taught courses on Hinduism. He has spent many years in India, which he first visited in 1977. He first engaged with yoga in the mid-1970s and lectures regularly on yoga and philosophy. He is also a song-writer and musician (Mahabongo).