William Burroughs closed his classic debut novel, Junky, by saying he had determined to search out a drug he called 'Yage' which he believed transmitted telepathic powers, a drug that could be 'the final fix'. In The Yage Letters - a mix of travel writing, satire, psychedelia and epistolary novel - he journeys through South America, writing to his friend Allen Ginsberg about his experiments with the strange drug, using it to travel through time and space, to derange his senses - the perfect drug for the author of the wild decentred books that followed. Years later, Ginsberg writes back as he follows in Burroughs' footsteps, and the drug worse and more profound than he had imagined.