The movie is infamous for being stuck here. Originally planned to go into production after Series VII, it got as far as having a script reading by the cast, filming dates announced and a prosthetic test for Robert Llewellyn. Unfortunately, thanks to continuing issues with funding, it never got any further than that. All that remains of the project is a test model shot using the Remastered ship, included on the Bodysnatcher Collection DVD set, and about 35 script drafts, with some of the ideas from the drafts reused as the series X episode, "The Beginning".
The series itself was originally supposed to be filmed and aired in 1987, but was delayed by an electricians' strike.
As Danny John-Jules loves to complain on DVD commentaries, there are many examples. Don't get him started on how everybody else's career took off except the main cast!
Cassandra, from the episode of the same name, is played by Geraldine McEwan (of Henry V and Robin Hood: Prince of Thieves fame).
Craig Charles lampshaded this when they were filming the reunion scene with Selby and Chen. He replied to Kryten's question, 'You know these people, sir?', exclaiming, 'Of course I do - they're in EastEnders!'
As is Kill Crazy, incidentally.
And now, so is Baxter.
The US pilots had a ton of these — Tom from Scary Movie 4 played Lister, Daphne Moon popped up as Holly, Jadzia Dax appeared as the second cat (the first was played by Hinton Battle, who isn't a particularly well-known actor but is pretty legendary in the world of dancing), and Kryten was played by... er, Robert Llewelyn, who was Kryten in the BBC series Red Dwarf.
Apparently, Hinton Battle is a hero of Danny John-Jules. Battle apparently put a lot of work into his version of The Cat, making John-Jules something of an Ascended Fanboy.
Holly, the ship's computer and most notable example, was played by Norman Lovett for Series I-II and was replaced by Hattie Hayridge for Series III-V before being Put on a Bus in Series VI. When the character returned for Series VIII (and the Series VII finale), Holly was once again played by Norman Lovett.
Kryten, the mechanoid, was a one-off character in Series II played by David Ross. When he became a regular in Series III, Ross was unavailable and Robert Llewellyn replaced him for the rest of the show's run.
Talkie Toaster (Exactly What It Says on the Tin) was voiced by John Lenahan in Series I and II (although his scenes were cut for the latter.) When the character resurfaced briefly in a Series IV episode ("White Hole"), not only was he voiced by David Ross (the original Kryten) but the original prop had been replaced as well.
Kristine Kochanski was a guest character in Series I, II and VI, and played by Clare Grogan. When the character became a main character in Series VII, Grogan was unavailable and ChloŽ Annett replaced her.
Rimmer's father was played by John Abineri in series II. After Abineri's death, in series X, he was played by Simon Treves.
The Pete Best: Kryten first appeared in a one-off appearance in Season 2 where he was played by David Ross. The character proved popular and opened up more storytelling possibilities, so Grant and Naylor decided to bring him back as a regular — Ross was unable to take the role due to scheduling commitments, however, so he was replaced by Robert Llewellyn (with a Hand Wave about how his appearance and personality was now different). Llewellyn proceeded to make the part his own, and even write some episodes.
Craig Charles's younger brother Emile plays Lister's 17-year-old younger self in "Timeslides".
Robert Llewellyn's wife Judy Pascoe plays the titular love interest's mechanoid form in "Camille".
Alexander John-Jules (Danny's nephew) as Baby Lister in "Ouroboros".
Recycled Script: "Trojan" is the basic premise of "Beyond a Joke" focusing on Rimmer instead of Kryten.
The Beginning takes several elements from a draft of the movie script.
Troubled Production: The making-of documentary for Series X makes the entire production process sound like an absolute nightmare for Doug Naylor. The fact that four episodes were shot whilst the remaining two were still being written thanks to significant production cock-ups on behalf of the producer is just the tip of the iceberg.
A deleted scene from Series II has the Cat and the Toaster singing a duet. Sadly, the Toaster's lines were never recorded.
The first series would have ended with the episode "Confidence and Paranoia", and would've had a cliffhanger ending with Kochanski being resurrected as a second hologram. But as the planned second episode "Bodysnatcher" just wasn't working, they scrapped it, rewrote the ending for "Confidence and Paranoia" to have a duplicate of Rimmer activated instead, and wrote the episode "Me^2" as a new series finale.
Similarly, the planned opener for the third series would've been an episode titled "Dad", which would've resolved the cliffhanger of Lister's pregnancy and re-introduced Kryten on-screen, as well as having Lister give birth to a single baby boy. Again, the episode wasn't working so it was scrapped and replaced by a comically-rapidOpening Scroll (which also resolved the "Where do the twins come from?" dangling plot thread for good measure).
A third Red Dwarf novel co-written by Grant and Naylor, titled The Last Human, was being planned before their writing partnership split. (Naylor later re-used the title for his own novel, even though the stories were different.)
The eighth series finale "Only the Good..." had four different endings altogether. The original ending (which was filmed but not used) was a happy ending where they saved the ship and took it back for themselves. The second ending (written, but not filmed) was a Downer Ending with Rimmer trapped aboard the disintegrating ship. The third ending involved Ace Rimmer coming to the rescue at the last minute — this was ready to be filmed, to the extent that Chris Barrie was in his Ace costume, before the broadcast ending was thought up and hastily thrown together.
And before that the final episode was to be entitled "Earth" and have a Bittersweet Ending where they returned to the homeworld, accidentally destroyed all our epic monuments trying to land, and finally Lister swaps insurance details with the survivors. They really couldn't afford it.
There was originally supposed to be more flashbacks in the style of Lister's one from "Balance of Power" to highlight Lister's loneliness.
In the commentary for the second episode, Chris Barrie mentions that he originally auditioned for both Rimmer and Lister, and *prefered* Lister. Imagine that for a moment. "Bodyswap", in fact, gives us a taste of how he would have played it.
Series X was initially intended to have 2 weeks worth of on-location shooting, 13 days of which had to be sacrificed in order to allow for the inclusion of a live studio audience for each episode. This also resulted in the cutting of two episodes that were going to use on-location footage heavily and feature a returning Kochanski as a prominent character.
There was, at one point, a Christmas Special in development, which never made it off the ground. Bill Pearson built a single model for it, which was recycled as the Simulant Death Ship in "The Beginning".
Word Of God: In a weekly podcast for the TV channel Dave, Doug Naylor explains that Rimmer was brought back as a hologram to keep Lister sane, and as a result his holo-computer makes it so he ages at the same rate as Lister. This neatly paves over the issue of how Rimmer doesn't age a day during his six hundred years on Rimmerworld and how hologram Rimmer ages at the same rate as Chris Barrie.