On the evening of March 20, 1974, a maroon Austin Princess carrying Princess Anne is forced off the Mall just 400 yards from Buckingham Palace. The man behind it, Ian Ball, carries two handguns and a plan to hold the Queen's daughter for a £3 million ransom. This film reconstructs the ten-minute struggle that follows minute by minute, using declassified documents and eyewitness testimony to show how a chauffeur, a police bodyguard, a passing journalist, and a former boxer intervened before Ball could force Anne into a second car. Three men are shot and wounded in the process, including the princess's protection officer. The documentary traces how the attack exposed gaps in royal security and led to lasting changes in how the royal family is protected in public. It is a close, procedural account of a single chaotic night rather than a broad biography, built around the people who happened to be nearby when it mattered.