Jin Shengtan wrote his commentaries to the novel Water Margin (Shuihuzhuan) between 1641 and 1644, during the final years before the fall of the Ming dynasty. These commentaries are exceptional at least in part because they reflect Jin’s frustrations that came from trying to understand this period of chaos. But they are also a good example of how fiction commentary helped to shape the trajectory that the development of Chinese fiction would take, in the form of commentaries and sequels. This article offers a reading of Jin’s commentaries to his 70-chapter edition of the Water Margin, to investigate how Jin radically reshaped the Water Margin as the masterpiece of a commentator of great literary genius. It analyses Jin’s rhetoric of controlling interpretation and concludes that Jin’s ultimate goal was to stabilize and prevent tampering of his “original” 70-chapter edition, in an attempt to close off future possibilities of “sequeling” the Water Margin.