Abstract: In Patrick McGrath’s novels, the gothic elements of transgression and decay create an essential framework for his characters who experience physical, mental, and moral breakdowns. In The Grotesque (1989), McGrath’s characters are also subject to grotesque forces, through which the boundaries between animal, human, and biological are transgressed. The narrative is grotesque as well. The genres that McGrath invokes and blends to create a grotesque narrative include the gothic, the grotesque, and a scientific narrative that highlights Charles Darwin’s ideas about evolution and natural selection. McGrath’s inclusion and fusion of these different narrative strands destabilize the social and class hierarchies that have empowered the protagonist and narrator, Sir Hugo Coal. The grotesque narrative also transforms the established social structures into systems that can adapt to changing conditions.