Throughout the history of the United States, only nine men were elevated to the White House by the death or failure of a sitting president, and their legacies are as mixed as their circumstances. This book evaluates the similarities and distinct differences of these men, their varying degrees of ambition and readiness, and how each handled their suddenly enormous duties. Some became presidential legends, while others are counted among the worst. Their shared stories shed light on America's political development during the last two centuries.