David Lloyd George is at Chequers for the weekend with his mistress Frances Stevenson, fretting about the fact that his involvement in selling public honours is about to be revealed by one Victor Grayson. Victor is a bisexual hedonist and former firebrand socialist MP turned secret-service informant. Intent on rebuilding his profile as the leader of the revolutionary Left, he doesn't know exactly how much of a hornet's nest he's stirred up. Doesn't know that this is, in fact, his last day.
No one really knows what happened to Victor Grayson - he vanished one night in late September 1920, having threatened to reveal all he knew about the prime minister's involvement in selling honours. Was he murdered by the British government? By enemies in the socialist movement (who he had betrayed in the war)? Did he fall in the Thames drunk? Did he vanish to save his own life, and become an antiques dealer in Kent?