Chapter 6 looks at the ways in which frenzy was weaponized during the many religio-political upheavals of the period. As a figure of speech, it offered rich material for English polemicists, who knew that questioning their opponents’ sanity was more effective than simply refuting their claims. As a literal diagnosis, frenzy also had a practical use: it could silence politically inconvenient people without making a show. This chapter shows how its conferral was used to justify the incarceration of prophets, mystics, and kings. Yet the diagnosis had one serious drawback: it gave its recipients the gift of innocence. Frantic persons were incapable of crime, and could neither be convicted nor punished for their actions. If a recipient later became not just inconvenient but too dangerous to live, any previous diagnosis – no matter how spurious – had to be redacted from the record. This was a problem for the religious polemicists too: the aim was to pathologize ‘heretics’ ‘papists’, ‘puritans’, and ‘sectarians’, not to excuse them from all wrongdoing. Eventually, this chapter argues, that flaw drove Anglican polemicists to abandon frenzy for a new diagnosis: ‘melancholy enthusiasm’.