On the night of 23 February 1820, twenty-five impoverished craftsmen assembled in an obscure stable in Cato Street, London, with a plan to massacre the whole British cabinet at its monthly dinner. The Cato Street Conspiracy was the most sensational of all plots aimed at the British state since Guy Fawkes' Gunpowder Plot of 1605. It ended in betrayal, arrest, and trial, and with five conspirators publicly hanged and decapitated for treason. Their failure proved the state's physical strength, and ended hopes of revolution for a century. Vic Gatrell explores this dramatic yet neglected event in unprecedented detail through spy reports, trial interrogations, letters, speeches, songs, maps, and images. Attending to the 'real lives' and habitats of the men, women, and children involved, he throws fresh light on the troubled and tragic world of Regency Britain, and on one of the most compelling and poignant episodes in British history.