 While snooping through Kristine Kochanski's quarters for her hologram disc, despite the fact they were not decontaminated, Dave Lister (Craig Charles) contracts a mutated strain of pneumonia.The condition causes Lister to become delirious and experience hallucinations, all of which become physical in presence, including fish raining in his sleeping quarters (which Cat (Danny John-Jules) later eats), and the Mayor of Warsaw from 1546 appearing and then spontaneously combusting.Arnold Rimmer (Chris Barrie) later reveals this to Lister, before stating that he also caused two men to appear in the Drive Room.