1. Bank Card

Hannah Fry takes a look at the bank card. This humble piece of plastic is often taken for granted, but it's the digital key to accessing cash and is packed full of extraordinary technological innovations - including some with surprising and sinister origins.....Hannah is granted the first ever TV access to Visa's European bank card data centre, discovers why we have Russian spies to thank for contactless payments, and finds out how the CIA and a 1950s housewife helped kick-start the bank card revolution.