Diana Mosley was one of Britain's most notorious fascist supporters and one of the few British aristocrats welcomed into Adolf Hitler's inner circle. Born into the famous Mitford family, she abandoned a privileged life to pursue a relationship with Sir Oswald Mosley, leader of the British Union of Fascists, and became one of the most devoted supporters of Nazi Germany.

The story follows Diana Mosley's journey from British high society to Nazi Germany, examining her friendship with Adolf Hitler, her secret wedding at Joseph Goebbels' home attended by Hitler, her close relationships with Magda Goebbels and Winifred Wagner, and her unwavering support for fascism before, during, and after the Second World War.

It also explores the rise of the British Union of Fascists, the Nuremberg Rallies, the Mitford family, MI5's surveillance, the internment of Diana and Oswald Mosley under Defence Regulation 18B, and her post-war life in exile in France. Despite the Holocaust and the defeat of Nazi Germany, Diana Mosley never publicly renounced her admiration for Hitler or her fascist beliefs, remaining one of the most controversial figures in modern British history.