In May 1940, the fate of Western Europe hangs on British Prime Minister Winston Churchill, who must decide whether to negotiate with Adolf Hitler, or fight on knowing that it could mean a humiliating defeat for Britain and its empire. As the unstoppable Nazi forces roll across Western Europe and the threat of invasion is imminent, and with an unprepared public, a sceptical King, and his own party plotting against him, Churchill must withstand his darkest hour, rally a nation and attempt to change the course of world history.