America's unique form of democracy separates power among three branches of government: the legislative, judicial and executive. As the head of the executive branch, the president of the United States is the country's most visible and important leader, both at home and abroad. Join HISTORY for a fresh perspective on how the Oval Office has evolved over the past 200 years through stories about the 43 men who have served as commander-in-chief. This eight-hour miniseries concentrates on the ebbs and flows of presidential power and responsibilities as each of America's leaders deal with the events, expectations and challenges of his time.