Teenager Billy Monger, AKA Billy the Whizz, was a rising star of British motorsport until a high-speed crash while racing in Formula 4 in 2017 resulted in a double leg amputation.

Just over a year on, Billy travelled to Rome to meet former F1 driver, two-time CART champion and four-time Paralympic handcycling gold medallist Alex Zanardi, who lost both of his legs in a crash in Germany in 2001.

'Human Endeavour: Billy Monger meets Alex Zanardi' on BBC World News from 1 September