The narrator presents the facts of the extraordinary case of his friend Ernest Valdemar, which have incited public discussion. He is interested in mesmerism, a pseudoscience involving bringing a patient into a hypnagogic state by the influence of animal magnetism, a process that later developed into hypnotism. He points out that, as far as he knows, no one has ever been mesmerized at the point of death, and he is curious to see what effects mesmerism would have on a dying person. He considers experimenting on Valdemar, an author whom he had previously mesmerized, and who has recently been diagnosed with phthisis (tuberculosis).