In the original teleplay for this episode, based on a Kirk-era novel "The Wounded Sky", Kosinski was responsible for both the warp effects and the accident and involved a hallucination in the form of the return of Jack Crusher (source - Star Trek - The Next Generation Companion).
	Erik Menyuk (The Traveler) originally auditioned for the role of Data.
	Worf's pet targ is actually a Russian wild boar wearing a garment designed by Bill Theiss.
	Kosinski has a square rank pin, which is never seen again on Star Trek.
	Dennis Madalone - famous for his stunt work on Star Trek - makes his first appearance in this episode as the crewman trapped by fire.

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