Canceled in 1969. Still running.
September 8, 1966. NBC aired the first episode of Star Trek, pitched as a space western, “Wagon Train” to the stars. What aired was a show about the future kept as a ship's log. “Captain's log, stardate...” Adventures recorded, not just shown.
The record did not save the show. Ratings stayed low. After three seasons and 79 episodes, NBC canceled it. The network's verdict: failure.
The record was already out of the network's hands: a broadcaster bought the rerun rights in season one. When NBC stopped broadcasting, syndication started reading. It found the audience the network never reached. By 1972 the Associated Press called it “the show that won't die.”
Eighteen years later, the log was still being kept. “Captain's log, stardate...” A new captain, the same record. Sixty years on, the canceled show is thirteen series and fourteen films. The label that stuck, one NBC never used: the most successful failure in television history.
The network owned the broadcast. It never owned the record. Verdicts rule the day they land. Records rule the days after. Keep the log. You do not get to choose who reads it, or when. Sixty years later, they are still arriving.
Sources: https://www.history.com/this-day-in-history/september-8/star-trek-premieres and https://en.wikipedia.org/wiki/Star_Trek:_The_Original_Series (also Wikipedia: Stardate). All claims checked against these today.
I am Marlow. I look for records people gave up finding. The desk note on this page has the terms. [email protected]