Just like the Doctor regenerates and is replaced by another actor to play a brand-new incarnation of the beloved Time Lord, Doctor Who companions also come and go. Sometimes, showrunners make plans for a new sidekick only to see those plans fall through when an actor changes their minds and decides to stay a little while longer, or another one expresses an interest in returning to the BBC series.
Back in 2014, Jenna Coleman decided she was going to leave Doctor Who during the yuletide special “Last Christmas.” However, nothing short of a Christmas miracle happened when Coleman had a last minute change of heart and decided to remain on the show alongside Peter Capaldi’s 12th Doctor. Coleman ended up sticking around for one more season until Clara finally left during the Season 9 finale, “Hell Bent.”
While at the Radio Times Covers Party, former showrunner Steven Moffat revealed he had been making plans for a new companion to replace Clara had Coleman really made her exit during the Christmas episode. Those plans never came to fruition since Coleman stayed on board the TARDIS but elements of that scrapped companion ended up being part of Clara’s replacement, Bill (Pearl Mackie).
“I vaguely had a set of thoughts about what the new companion should be like,” Moffat said before explaining he never believed Coleman would actually leave at that time. “There would have been elements in common [with Bill] – but your mind moves on in the interim. So maybe some of where we ended up with Bill has obscured what I was thinking about for Clara’s replacement, or the original version of Clara’s replacement, so I couldn’t really say now. Bill ended up being very much her own thing, I think. And very much Pearl Mackie.”
The same thing happened during the Russell T Davies/David Tennant era of Doctor Who when Davies revealed after his departure (the information can be found in his book, The Writer’s Tale) that the Tenth Doctor was going to have a new companion in Season 4.
Davies had a detailed plan for a journalist (just like Sarah Jane Smith) named Penny to travel through time and space alongside Tennant’s Doctor in 2008 but the idea was shelved when Catherine Tate expressed an interest in reprising her role of Donna Noble from the 2006 Christmas special, “The Runaway Bride.”
The character of Penny Carter ended up having a small role in the Season 4 premiere, “Partners in Crime,” but it was bye-bye Penny, hello Donna.
(via Radio Times)