A band,
featured in "Trekkies 2" named themselves "No Kill I" after the
Horta's ominious message.
Barry
Russo, who plays Lieutenant Commander Giotto, would later play
Commodore Robert Wesley in
"The Ultimate Computer".
William
Shatner's father passed away during the shooting of this episode,
causing him to lose a couple days of filmmaking.
This is
William Shatner's favourite episode.
After
returning from his father's funeral, William Shatner asked Leonard
Nimoy to go through the scene where Mr. Spock reaches out with his
mind to communicate with the Horta, since the scene had already been
filmed with Shatner's stunt double's back to the camera. After Nimoy
screamed "PAIN, PAIN!", William Shatner chimed in "Someone get this
man an aspirin!" Leonard Nimoy didn't take too kindly to that.