Hollywood glamour. The aristocracy. Britain's political elite. One legendary nightclub. In June 1935, a discreet door opened on Leicester Square. Behind it lay The 400 Club - an intimate basement sanctuary where over three decades Hollywood's biggest stars partied with royalty, the British aristocracy and prominent politicians in spectacular fashion. Here, beneath the soft glow of Art Deco lighting, Marlene Dietrich shared champagne with dukes, Douglas Fairbanks Jr. wooed his latest conquest and Princess Margaret slipped in and out unnoticed through a hidden exit in the early hours. Surviving the Blitz, navigating wartime rationing and hosting everyone from Clark Gable to Churchill's inner circle, The 400 Club became the beating heart of London's high society. And at its centre was manager Gaudenzio Rossi personally vetting every application, ensuring the Club's reputation for exclusivity - and discretion - remained unmatched. But by the swinging sixties, the world had changed. The old guard was dying and the young wanted something different. New clubs challenged the 400's supremacy and scandals threatened its mystique. Gaudenzio Rossi had retired and new owners failed to keep up with the changing times. When the 400 Club's doors closed for the last time in 1966, it was truly the end of an era. Now drawing on newly discovered archives and private correspondence, The 400 Club reveals the extraordinary true story of the nightclub which for three decades - through war and peacetime - was the epitome of glamour, fashion, fun and discretion and where the twentieth century's most fascinating characters came to play.