In 1943, the year in which the first A-bomb was built, Albert Hofmann discovered LSD, a substance that was to become an A-bomb of the mind. Fractions of a milligram are enough to turn our framework of time and space upside down. The story of a drug - its discovery in the Basel chemistry lab, the first experiments by Albert Hofmann on himself, the 1950s experiments of the psychiatrists, the consciousness researchers, the artists. Could it actually be possible to find a path to the core of our human existence by means of a chemical? Spirituality at the flick of a switch? Do the enigmatic effects of this drug really help us to better understand the human soul? Could LSD be an instrument of contemporary psychiatry? Of modern brain research?