The demonic plays an integral role in the Shahnameh, manifesting itself in countless forms. Early kings and heroes fight demons at every turn, and in one of the most memorable tales in the poem—the story of Zahhāk—Iran itself falls under the rule of demonic forces. But demons are not always physical creatures; we also encounter them as immaterial forces of temptation, distraction, and fate. One of the most fascinating aspects of this multifarious presentation of the demonic is the way it intersects the poem's portrayal of what it means to be human. This article focuses on that intersection, highlighting encounters between human beings and the demonic and arguing that they not only complicate notions of humanity, but also construct and reinforce categories of masculinity and femininity. A close examination of two phenomena at the heart of human–demon contact—serpents and sorcery—reveals how evil is embodied and enacted in highly gendered ways. Male and female characters in the Shahnameh diverge in their abilities to combat the demonic and are lured into wickedness by different means. What emerges from the interplay between human beings and demons and between the categories of masculinity, femininity, and the demonic is a multifaceted and sophisticated portrayal of evil that informs even the simplest and most straightforward tales in Ferdowsi's work.