Todd Sampson began his TV career on Gruen, the long-running ABC series about advertising, before transforming himself into a human guinea pig to scrutinise the limits of the human brain and body.His upcoming show, called Why?, explores the reasons behind why people turn to extreme beliefs and behaviours such as doomsday prepping, base-jumping or alien worship. In this chat, hosted by The Sydney Morning Herald science reporter Angus Dalton, Sampson talks about his upbringing, how he went from 'ad man' to TV, and the moment marrying a doomsday prepper really came in handy.

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