"Jeffty Is Five" is a fantasy short story by American writer Harlan Ellison. It was first published in The Magazine of Fantasy & Science Fiction in 1977, then was included in DAW's The 1978 Annual World's Best SF in 1978 and Ellison's short story collection Shatterday two years later. According to Ellison, it was partially inspired by a fragment of conversation that he mis-heard at a party at the home of actor Walter Koenig: "How is Jeff?" "Jeff is fine. He's always fine," which he perceived as "Jeff is five, he's always five." Additionally, Ellison based the character of Jeffty on Joshua Andrew Koenig, Walter's son.
... I had been awed and delighted by Josh Koenig, and I instantly thought of just such a child who was arrested in time at the age of five. Jeffty, in no small measure, is Josh: the sweetness of Josh, the intelligence of Josh, the questioning nature of Josh.
"Jeffty is Five" concerns a boy who never grows past the age of five — physically, mentally, or chronologically. The narrator, Jeffty's friend from the age of five well into adulthood, discovers that Jeffty's radio plays serial programs no longer produced on radio stations that no longer exist. They are contemporary, all-new shows, however; not re-runs. He can buy comics such as The Shadow and Doc Savage that are, again, all-new although they are no longer being produced, not to mention long discontinued pulp magazines with new stories by Stanley G. Weinbaum, Edgar Rice Burroughs and Robert E. Howard despite the authors being long dead. Jeffty can even watch films that are adaptations of old pulp fictionnovels like Alfred Bester's The Demolished Man. The narrator is privy to this world because of Jeffty's trust, while the rest of the world (the world that grew as Jeffty did not) is not. When Jeffty's world and the "real" world intersect Jeffty loses his grip on his own world, eventually meeting a tragic end.