In 1820 five men, convicted of treason, were publicly hanged and beheaded before Newgate Prison. Their crime, it was alleged, involved to do away with the entire British Cabinet at one stroke. What had driven the conspirators to so drastic a course? How were their plans discovered in time to avert the coup d'état?

It was in a dilapidated room over a disused stable, still standing in Cato Street off London's Edgeware Road, that Thistlewood, a name assumed by an ex-soldier and notorious malcontent, collected together his small band of collaborators. At first their aims were diffuse and lacked unity of purpose, until Edwards, who appeared to be Thistlewood's deputy, began to urge them on to violent action. It was he who finally produced the newspaper cutting announcing the first Cabinet dinner since the late King's death. As the police converged on Cato Street, arms were being distributed among the conspirators. There ensued a brief but bloody battle; one of the constables was run through with a sword and others were wounded before nine of the rebels were taken into custody. Thistlewood escaped with a price on his head, but was later arrested at a hideout Edwards had found for him. Edwards himself, who had not been present at the Cato Street raid, slipped quietly away and was never seen again.

Repeatedly Counsel for the Defence insisted that the Crown produce Edwards as a witness, for it seemed clear that the case rested as much on his evidence as any, yet no attempt was made to bring him in. Could he have been an agent provocateur? Were the condemned men victims of a Government-inspired counter-plot?

John Stanhope brilliantly illuminates this murky corner in British history. The plot, no less–and no more–violent in its outcome than of Guy Fawkes, has not until today been fully exposed in all its strange ramifications.