Book excerpt: The Lord of the Rings, Star Wars, and certain other works of fantasy and science fiction have inspired some of their readers and viewers to believe that the superhuman powers of the story-worlds, such as Gandalf and the Force, exist also in the real world. We can say that such fictional narratives possess 'religious affordance', for they contain certain textual features that afford or make possible a religious, rather than just a fictional, use of the text. This book aims to identify those features of the text that make it possible for a fictional narrative to inspire belief in the supernatural beings of the story, or even to facilitate ritual interaction with these beings. The contributions analyse the religious affordance and actual use of a wide range of texts, spanning from Harry Potter and Star Wars, over The Lord of the Rings and late 19th-century Scandinavian fantasy, to the Christian Gospels. Although we focus on the religious affordance of fictional texts, we also spell out implications for the study of religious narratives in general, and for the narrativist study of religion. This book was originally published as a special issue of the journal Religion.