The process of adaptation necessarily engages the technologies of the chosen media and associated ideas of medium specificity. In adapting works between media, producers must negotiate between fidelity to the source and perceived specificities of the chosen technological medium. The adaptation for British Broadcasting Corporation television of the 2004 novel Jonathan Strange and Mr Norrell by Susanna Clarke reminds us of the growing complexity in the relations between what, until comparatively, have been understood and interpreted as the separate media of film and television, and their relation to the novel. The technological basis of media and the idea of medium specificity may thus be seen as central both to adaptation as a process and to critical engagement with adaptations as texts. Adaptation, as a practice that actively engages with the media it crosses between, can be seen as a crucible for these wider concerns and thus a pertinent focus for this investigation.