This book explores the vast array of animals that populate detective fiction. If the genre begins, as is widely supposed, with Edgar Allan Poe’s “Murders in the Rue Morgue” (1841), then detective fiction’s very first culprit is an animal. Animals, moreover, consistently appear as victims, clues, and companions, while the abstract conception of animality is closely tied to the idea of criminality. Although it is often described as an essentially conservative form, detective fiction can unsettle the binary of human and animal to intersect with developing concerns in animal studies: animal agency, the ethical complexities of human/animal interaction, the politics and literary aesthetics of violence, and animal metaphor. Gathering its 14 essays into sections on ontologies, ethics, politics, and forms, Animals in Detective Fiction provides a compelling and nuanced analysis of the central role creatures play in this enduringly popular and continually morphing literary form.