Denise Crosby's dissatisfaction with her role as Yar was well known with the media of the time. Crosby preferred to bow out on friendly terms with her colleagues, enabling her to pursue a film career.
	The death scene was originally slated to occur much earlier in the episode, with the rest of the hour focusing on Armus, and none of the farewell scenes included, but Gene Roddenberry overruled.
	It was originally planned that the away team would kill Armus in the end, but Roddenberry thought it was not befitting of 24th Century humans to kill just for the sake of revenge.
	Director Joe Scanlon famously said to the special effects team "If we don't make this monster believable, we're in deep shit".
	A Grave-size pit 10 feet deep had to be dug on the show's Planet Hell set and a hydraulic lift inserted to facilitate the rising of Armus. The black goo mix included Metamucil which weighed so heavy on actor Mart McChesney's costume that it disintegrated and a new one had to be constructed.
	Marina Sirtis began sobbing uncontrollably during the filming of Yar's farewell scene leading to several reshoots.
	Crosby later regretted leaving the series, saying that if more scenes like those between her and Worf at the start of the episode were written, she would have stayed. Crosby later made several reappearances through some very bizarre plot lines.
	During the scene where Commander Riker is pulled into Armus' tar pit, actor Jonathan Frakes was actually submerged in a pool of printer's ink

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