"King Nine Will Not Return" is the season two premiere episode, and 37th overall, of the American television anthology series The Twilight Zone. It originally aired on September 30, 1960 on CBS.

The Twilight Zone is an American fantasy science fiction horror anthology television series created and presented by Rod Serling, which ran for five seasons on CBS from October 2, 1959, to June 19, 1964. Each episode presents a standalone story in which characters find themselves dealing with often disturbing or unusual events, an experience described as entering "the Twilight Zone", often with a surprise ending and a moral. Although often considered predominantly science-fiction, the show's paranormal and Kafkaesque events leaned the show much closer to fantasy and horror. The phrase "twilight zone" has entered the vernacular, used to describe surreal experiences.