May, 1940. Britain is at war. The horrors of blitzkrieg have seen one western European democracy after another fall in rapid succession to Nazi boot and shell. Invasion seems mere hours away.

Just days after becoming Prime Minister, Winston Churchill must deal with this horror—as well as a skeptical King, a party plotting against him, and an unprepared public. Pen in hand and typist-secretary at the ready, how could he change the mood and shore up the will of a nervous people?

In this gripping day-by-day, often hour-by-hour account of how an often uncertain Churchill turned Britain around, the celebrated Bafta-winning writer Anthony McCarten exposes sides of the great man never seen before.

He reveals how he practiced and re-wrote his key speeches, from ‘Blood, toil, tears and sweat’ to ‘We shall fight on the beaches’; his consideration of a peace treaty with Nazi Germany, and his underappreciated role in the Dunkirk evacuation; and, above all, how 25 days helped make one man an icon.

Using new archive material, McCarten reveals the crucial behind-the-scenes moments that changed the course of history. It’s a scarier—and more human—story than has ever been told.