Contested science presents a problem for ‘evidence-based’ public health intervention. Taking a perspective that treats evidence as constituted through the practices which make it, we treat controversies in public health science as events of ‘evidence-making’ intervention. We look back on a recent controversy in evidence-making regarding the curative potential of new treatments for hepatitis C. The controversy concerned the publication of a systematic review conducted by the Cochrane Collaboration. We explore how published responses critical of the review enact their evidence-making. We do this to illuminate how moments of controversy offer useful sites of evidencing-making investigation for public health research. We identify four intersecting objects of evidence-making in the published responses: cure; expertise; hope; and morality. We reflect on how different experts perform evidence differently, how these evidence performances are in friction yet incorporate one another, and how such evidence-making practice fuses together different knowledge forms within and beyond science. Controversy makes visible the multiplicity and fluidity of evidence objects which might otherwise be constituted as singular and robust. A prime matter of concern in this exemplar is ‘cure’ and the protection of curative potential linked to new treatments in the presence of evidence uncertainty. We use our case study to argue for the benefits of an ‘evidence-making intervention’ approach to the study and use of evidence in critical public health research.