The story begins with the unnamed narrator arriving at the house of his friend, Roderick Usher, having received a letter from him in a distant part of the country complaining of an illness and asking for his help. Although Poe wrote this short story before the invention of modern psychological science, Roderick's condition can be described according to its terminology. It includes a form of sensory overload known as hyperesthesia (hypersensitivity to textures, light, sounds, smells and tastes), hypochondria (an excessive preoccupation or worry about having a serious illness) and acute anxiety. It is revealed that Roderick's twin sister, Madeline, is also ill and falls into cataleptic, death-like trances.