This article examines the thematic and formal materiality of Swedish writer Sam J. Lundwall’s multimodal novel Fängelsestaden (1978). The book is illustrated by Giovanni Battista Piranesi’s Carceri etchings from 1761, but is also inspired by them, which engages the reader as part of a media ecology of text, visual art, and more. The participatory aesthetics is further highlighted by metaleptic elements within the text, as well as the unimportance of humanity compared to the city itself being a major theme. A conclusion is that the novel thematizes materiality at the same time as being an example of the dissolution of the borders between human and animal, mind and body, nature and culture, and, especially, form and content.