In describing his scientific study of DMT (the hallucinogen prominent in many Amazonian psychedelics) in a university hospital in the 1990s, the author discusses its chemical properties, the process by which the study was approved, how the study was run in detail, the psychological effects and experiences, and concludes that in itself the drug is not beneficial, but that all depends upon the context in which it is taken and what the person involved brings to the experience. To me it was especially interesting that animals, including humans, naturally produce DMT in their bodies (some plants do also). Does it have a role in facilitating in the way we naturally perceive the world? Also, that people given the drug experienced not only "psychedelic" and near-death-like experiences, but also "alien contact" experiences indistinguishable from those reported by people claiming alien abduction, surprised and disturbed the author. I would have preferred to focus on just the drug's properties and effects, and the author's conclusions, instead of having so much information about his setting up and running the study.