After his dramatic rise to power in the summer of 2019 amid the Brexit deadlock, Boris Johnson presided over the most turbulent period of British history in living memory. Beginning with the controversial prorogation of Parliament in August and the historic landslide election victory later that year, Johnson was barely through the door of No. 10 when Britain was engulfed by a series of crises that will define its place in the world for decades to come. From the agonising upheaval of Brexit and the devastating Covid-19 pandemic to the nerve-shredding crisis in Afghanistan and the outbreak of war in Ukraine, Johnson's government ultimately unravelled after just three years. This gripping behind-the-scenes work of contemporary history maps Johnson's time in power from start to finish and sheds new light on the most divisive Prime Minister to have led the United Kingdom since Thatcher. Based on more than 200 interviews with key aides, allies and insiders, Johnson at 10 gives the first full account of Johnson's premiership, the shockwaves of which are still felt today.