McCalman explains the process he underwent to transform his historically accurate portrayal of the life of Count Cagliostro into a work that would be accessible to, and popular with, non-specialist readers. His technique was to borrow from the structures of literary fiction, thereby preserving 'the suspense and pace of the story without compromising [his] core beliefs about what a historian can truthfully say about the past.' McCalman acknowledges that his editor and some reviewers were left wondering whether he was writing history or fiction.