Peter Ackroyd's writing is obsessed with the defining heterogeneity of London - its rich diversity of human experience, mood, and emotion, of actions and events, and of the tools through which all of this heterogeneity is represented and reenacted. But for Ackroyd, one of the foremost of the so-called 'London writers,' this energizing heterogeneity also has a sinister side, largely originating outside social norms and mainstream pathways of cultural production. Touching on everything from occult practices to the plotting of radical groups, crime and fraud, dubious scientific experiments, and popular, dramatic forms of ritual and entertainment, Ackroyd contends that these forces both contest prescribed cultural modes and supply the city with its characteristic dynamism and capacity for spiritual renewal.