It was, truth be told, an inelegant ending. Star Trek: The Original Series wrapped its run on June 3, 1969 with the episode "Turnabout Intruder," a mad-scientist hour and, in the view of pretty much everyone, a rather sexist installment for such a progressive series. Still, it holds an important place in Star Trek history and, as such, StarTrek.com shares 6 Things to Know About "Turnabout Intruder."
Wallerstein's Fourth Trek
"Turnabout Intruder" was directed by Herbert Wallerstein, who'd earlier helmed "The Tholian Web," "That Which Survives" and "Whom Gods Destroy." Sadly, Wallerstein died in 1985 at the age of 59, having been beaten to death by his housekeeper, who claimed she was defending herself.
The story outline for "Turnabout Intruder" was tapped out in April of 1968... by Gene Roddenberry.
The LEMLI Connection
The character of Lemli was played by Roger Holloway. He'd portrayed Starfleet crewman many times before, sans dialogue or a character name or dialogue. He actually spoke two words in the series finale and was named Lemli. No doubt not coincidentally, William Shatner's licence plate back then read LEMLI -- a mix of his daughters' names: Leslie, Melanie and Lisabeth -- and to this day his production company is called Lemli Productions.
NBC planned to air "Turnabout Intruder" on March 28, 1969. Sadly, former President Dwight D. Eisenhower had died, prompting NBC to bump the episode... to June.
Jeffrey Hunter, who exited Trek after filming "The Cage," died on May 27, 1969, a week before "Turnabout Intruder" premiered. Just imagine how different Star Trek might have been if he'd continued to play Captain Pike. Would there ever have been TOS movies or spinoffs?
In the Next Generation episode "Legacy," Captain Picard comments that the Enterprise is bypassing an archeological survey on Camus II, precisely where the action in "Turnabout Intruder" started. That was TNG's sly tip tribute to TOS, as it marked the 80th episode of TNG, surpassing TOS, which ended after 79 episodes.