Graham Hancock tells the story of his 24-year relationship with cannabis brought to an abrupt halt in 2011 after an encounter with ayahuasca, the sacred visionary brew of the Amazon. Along the way he explores the mystery of death, the problem of consciousness, and the implications for the human future of a society that wages total war on true cognitive liberty.

Graham Hancock is the author of The Sign and the Seal, Fingerprints of the Gods, Keeper of Genesis, Heaven's Mirror, Supernatural and other bestselling investigations of historical mysteries.

His books have been translated into twenty-seven languages and have sold over five million copies worldwide. His public lectures and broadcasts, including two major TV series, Quest for the Lost Civilisation, and Flooded Kingdoms of the Ice Age, have further established his reputation as an unconventional thinker who raises controversial questions about humanity's past. Hancock's first venture into fiction, Entangled, was published in 2010 and his second novel, War God, on the Spanish Conquest of Mexico, will be published on 30 May 2013. Hancock maintains an active Facebook presence: His website is:

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