Recently many people have shown great interest in traditional indigenous practices and popular medicine, involving the ingestion of natural psychotropic drugs. We received a request to analyze and determine the nature of a dark green liquid with a dark brown plant sediment, which the police had seized at an airport and inside the home of a person belonging to the ‘Santo Daime’ religious movement. Gas chromatography/mass spectrometry analysis of the extract identified N,N- dimethyltryptamine, a potent hallucinogen, and the β-carboline alkaloids harmine and harmaline, revealing monoamine oxidase A-inhibiting properties. These substances are typical components of Ayahuasca, a South American psychotropic beverage obtained by boiling the bark of the liana Banisteriopsis caapi together with the leaves of various admixture plants, principally Psychotria viridis.