Ben Jonson’s Catiline His Conspiracy (1611) has long been considered boring—and, sometimes, very bad. This chapter, by contrast, reveals both the play’s weird artistic achievement and its thematic illumination of Jonson’s comedic masterworks. It does so by attending to the discursive weaponization of “madness”—or furor—that structures the text. For Catiline is a drama not of tragic madness but madnesses—of rebels beset by a dizzying range of deviant psychologies, even as their leader Catiline asserts the group’s somatopsychic fitness to rule. Besting him at last is Cicero, who more persuasively appropriates the concept of furor, though only by talking in faulty binary terms—the cure of sanity, the menace of singular madness—which paint every conspirator with the same ample brush. Cicero's enemies soon clap back with their own charges of deceit and frenzy until it becomes clear that the consul himself will fall prey to the rigid mental standards with which he ensnared his foes. The ultimate tragedy of Jonson’s text, then, is that while Cicero initially wins with furor, his ableist thinking will at last effect his demise, and that of the city of Rome. Coming to terms with this paradox, I argue, impels us to revisit our habit not only of dubbing Jonson a neat, neoclassical moralist but also of politicizing the rhetoric of mental disability today.