 When the episode was remastered, Doug Naylor opted to change the ending of the story – in the remastered version, the second Polymorph makes its appearance as a bouncing ball, whereupon a caption explains that it was less intelligent as the first, stowed away in Lister's clean underpants drawer, and died of old age many years later.Naylor stated the change of ending was due to his dislike of fans asking him about the second creature's fate in the original ending.Director Ed Bye drew inspiration for the look and design of the episode from watching the 1979 film "Alien" just before shooting began.