On 11 May 1812 Spencer Perceval, the British Prime Minister, was fatally shot at close range in the lobby of the House of Commons. In the confused aftermath, his assailant, John Bellingham, made no effort to escape. A week later, before his motives could be examined, he was tried and hanged.

Here, for the first time, the historian Andro Linklater looks past the conventional image of Bellingham as a 'deranged businessman' and portrays him as an individual, driven by the anxieties of his family life, by his yearning for respectability and by the raw emotions that convulsed his home town of Liverpool. But as the evidence accumulates, a wider, darker picture emerges. The wildly unpopular Perceval dominated political life as both Prime Minister and Chancellor of the Exchequer. He, above all, was responsible for oppressing Luddite protestors, for Britain's naval blockade of Napoleonic France, for risking war with the United States. And, almost single-handedly, he was crushing Liverpool's illegal slave-trade.

John Bellingham was not alone in hating the prime minister. But did he act alone when he shot Spencer Perceval? And if not, who aided him? Two hundred years later, Andro Linklater examines Bellingham's personal records, his wife's letters and the reports of the Bow Street Runners, London's first detective agency, uncovering strange payments made to the murderer and an untouched historical trail. Catching the threads of conspiracy amid the fevered tone of an age of intense debate over slavery, security of the state and personal liberty, Linklater brilliantly deconstructs the assassination of Spencer Perceval - the only British Prime Minister ever to have suffered that fate - to offer a fresh perspective on Britain and the Western world at a critical moment in history.