This is the last of a three‐part review of Kyle Harper's The Fate of Rome. Here, we scrutinize Harper's treatment of the Justinianic Plague, demonstrating how he crafts a convincing narrative based on rhetorical flourishes but little evidence. We call further attention to several internal contradictions within the chapter and misinterpretations of evidence. We conclude this series of articles with a reflection on Harper's deterministic approach to environmental history. While the environment appears everywhere, agency (people: society and culture) is mostly absent. We finish by emphasizing the need to develop more nuanced causal explanations for complex historical processes and suggest that future attempts to bring together such wide‐ranging material be done within interdisciplinary research teams.