 The heat-seekers were given sound effects borrowed from the lightsabers of "Star Wars".Guest appearances included actress Frances Barber who took on a scene as 'Genny Mutant', Kalli Greenwood, who played Rimmer's mother, and the show's first appearance of Rimmer as a young boy, played by Simon Gaffney.The theme of the episode is a parody of Ridley Scott's 1979 "Alien" film which features a Xenomorph.