This article examines the emergence and constitution of a new affliction category in contemporary Egypt: wahm, meaning (self-)illusion, locally defined as the condition of being falsely convinced one is possessed by spirits called ‘jinn’, all the while exhibiting real possession symptoms. As I show, wahm transcends the domain of revivalist Islamic healing from where it originates by mobilizing and entangling Islamic and psy concepts and practices. It both exploits the local dichotomy of jinn afflictions/mental disorders and grows from the cracking of this binary. In this manner, wahm provides a new idiom for critiquing current therapeutic practices, for understanding suffering, and for analyzing modern life in today’s Egypt. Through the analysis of wahm, this article contributes to scholarly investigations of ontology and the emergence of diseases by moving the lens from biomedical categories to the terrain where biomedicine meets religious healing, highlighting not only intersections but also the new formations they engender.