On the surface the plot follows the story of a penniless, starving author called Geoffrey Tempest. So poor that he is behind on his rent and can barely afford light in his room, he receives three letters. The first is from a friend in Australia who has made his fortune and offers to introduce him to a good friend who might be able to lift him from poverty. The second is a note from a solicitor detailing that he has inherited a fortune from a deceased relative. The third is a letter of introduction from a foreign aristocrat called Lucio, who befriends him and proceeds to be his guide in how best to use his newfound wealth.<br />Tempest remains blissfully unaware throughout the novel, despite warnings from people he meets, that Lucio is the earthly incarnation of the&nbsp;Devil.