A former stock market millionaire and ecstasy supplier visited Orleans Park School with a cautionary tale of prison and drugs.
Shaun Attwood, who is now a public speaker, author and activist, spoke about his life to year 12 pupils at the Twickenham school.
His story was featured on the National Geographic channel as part of an episode of Banged Up Abroad.
Having been a raver in the 80s in Manchester, he travelled to the US, a country he has now been banned from for life, to throw raves and import ecstasy.
Mr Attwood has appeared on the BBC, Sky News and TV worldwide.
Random House published his life story as the English Shaun Trilogy: Party Time, Hard Time and Prison Time.
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