In this article, the origins of the cult of the ritual drink known as soma/haoma are explored. Various shortcomings of the main botanical candidates that have so far been proposed for this so-called “nectar of immortality” are assessed. Attention is brought to a variety of plants identified as soma/haoma in ancient Asian literature. Some of these plants are included in complex formulas and are sources of dimethyl tryptamine, monoamine oxidase inhibitors, and other psychedelic substances. It is suggested that through trial and error the same kinds of formulas that are used to make ayahuasca in South America were developed in antiquity in Central Asia and that the knowledge of the psychoactive properties of certain plants spreads through migrants from Central Asia to Persia and India. This article summarizes the main arguments for the botanical identity of soma/haoma, which is presented in my book, The Tawny One: Soma, Haoma and Ayahuasca (Muswell Hill Press, London/New York). However, in this article, all the topics dealt with in that publication, such as the possible ingredients of the potion used in Greek mystery rites, an extensive discussion of cannabis, or criteria that we might use to demarcate non-ordinary states of consciousness, have not been elaborated.