This article explores how occult and medical epistemologies intersected in late Victorian and Edwardian courtroom narratives in the Old Bailey, London's Central Criminal Court. Rather than delineating the preternatural, I argue that this meeting of the occult and medical science resulted in a blurring of the boundaries between external and internal influences, between notions of prisoner and patient, the psychical and the insane. Considering the role of the accused, victims, medical authorities, lawyers, and jurors, I examine how this epistemological shift developed and how it was presented, manipulated, or hindered. Through investigating this attempt by medical “experts” to pathologize the occult, I offer fresh insights into how medical testimony interpreted and employed accounts of witchcraft, mesmerism, and hypnotism in courtroom narratives. I conclude by briefly drawing attention to the resonances between the operation of occult, legal, and medical influences over the mind and body in the late nineteenth-century courtroom.