A royal high-flier, diplomat, and daredevil pilot, Prince William of Gloucester was once seen as one of the monarchy's brightest hopes. But in 1972, the Queen's charismatic cousin was killed when his plane crashed during an air race, cutting short a life of privilege, romance, and risk. Featuring rarely seen archive and first-hand accounts, this compelling documentary revisits the story of a royal who lived fast and died young - and explores whether his untimely death quietly reshaped the future of the modern monarchy.