The novel's protagonist and narrator, David Martín is a mystery writer born in Barcelona, Spain, in 1900. Born into poverty and cared for by an abusive, drug-addicted father, David escapes into literature as a refuge. At the age of 14, David's father is gunned down in front of the newspaper office where he works as a night watchman. Taking pity on David, one of the newspaper's wealthy owners, Pedro Vidal, sets up David with a job and fosters his career as a writer.

One of David's defining characteristics is his unreliability as a narrator. While it is an open question whether David is psychotic and the supernatural events around him hallucinations, there is little doubt that David's vanity—represented symbolically by his love for the book Great Expectations—distorts his perceptions of himself. This is partly why the Satan figure of Corelli so easily manipulates David into helping him write a religion aimed at causing massive amounts of death and destruction around the world. In fact, if one interprets events as a product of David's fevered, narcissistic personality, then the whole of the narrative becomes about a vain, embittered writer who, jealous of his friend's wealth, romantic successes, and literary achievements, takes credit for writing his hit novel.