Infinite Intruder is a 1953 science fiction short story by Alan E. Nourse. When Roger Strang found that someone was killing his son—killing him horribly and often—he started investigating. He wasn't prepared to find the results of another investigation—this time about his own life. Infinite Intruder was first published in Space Science Fiction July 1953. Alan Edward Nourse (1928-1992) was an American science fiction author and physician. He wrote both juvenile and adult science fiction, as well as nonfiction works about medicine and science. His SF works generally focused on medicine and/or psionics. Psionics refers to the practice, study, or psychic ability of using the mind to induce paranormal phenomena. Examples of this include telepathy, telekinesis, and other workings of the outside world through the psyche. His novel The Bladerunner lent its name to the Blade Runner movie, but no other aspects of its plot or characters, which were taken from Philip K. Dick's Do Androids Dream of Electric Sheep?