Many don't realise just how much we rely on opium and the drugs we derive from it – drugs which have the power to both relieve and inflict pain.
Thousands of people have used opium in some way – many have had controlled, monitored doses of medication, while others have fallen into the dangerous clutches of addiction.
Brian Cox went on a journey to uncover the rich, provocative history of opium and to discover how a simple plant became a hugely profitable global commodity.
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