People narrating the experience of dysregulated anger after a brain injury call upon metaphor in patterned ways to help them make sense of their situation. Here, I analyze the use of the metaphor of the doubled self in a personal narrative of brain injury, and I situate this metaphor in its cultural history by analyzing Dr Jekyll and Mr Hyde and The Incredible Hulk as landmark moments in its development. A pattern of thought reflecting Seneca's philosophy on the incompatibility of anger with rational selfhood emerges. I discuss implications for the way we care for people struggling with post-brain-injury anger.