ship's crew without realizing they had been long dead; bound by his "behavioural protocols", he is taught independent thinking by Lister and leaves the Red Dwarf on a space-bike to enjoy his newfound freedom. Between series 2 and 3, he is rescued by the crew after his space-bike crashed on an asteroid, and has become part of the Red Dwarf crew; however, the accident led to his face appearing permanently different. Categorized as a "series 4000 service mechanoid", he keeps on maintaining the Red Dwarf, while also showing himself very resourceful due to his proficiency with technology and encyclopedic knowledge of the universe; he maintains a strong friendship with Lister throughout the series. Clare Grogan (recurring series 1; guest series 2, 6) and Chloë Annett (regular series 7-8; guest series 9) as Kristine Kochanski:A navigation officer in the original Red Dwarf crew whom Lister had a crush on (later retconned to be his ex-girlfriend) and whose memory he had cherished ever since. After appearing in several episodes following her death, once directly due to Lister time travelling and later as various individuals impersonating her, an alternate version of Kochanski from a universe in which she, not Lister, is the last living human, joins the series' main universe and the Red Dwarf crew in the series 7 episode "Ouroboros". As part of the crew, she progressively gets closer to Lister, while struggling to overcome her past romantic relationship with her original universe's Lister, and has a conflictual relationship with Kryten, who is jealous of the interest Lister has for her. Between series 8 and 9, she is no longer part of the crew, and is believed by Lister to be dead; it is later revealed that she had actually fled the ship when it became clear Lister's complete lack of self-respect and indulgence on excesses was slowly killing him, which greatly depressed her; Kryten, the only one aware of her departure, pretended to have witnessed her death to avoid hurting Lister's feelings even more. After learning the truth, Lister hopes to reunite with her one day. In addition to Grogan and Annett, Suzanne Rhatigan and Anastasia Hille portray false versions of Kochanski in episodes of series 4 and series 5 respectively, while Holly Earl portrays a younger version of her in an episode of series 8. Production The first series aired on BBC2 in 1988. Eleven full series and one miniseries