Outgoing Doctor Who showrunner Steven Moffat has revealed that there was an alternative ending that he had originally planned for the show's 50th anniversary special.
The episode 'The Day of the Doctor' featured plenty of cameos from across the Doctor Who universe - most notably a return for David Tennant's Tenth Doctor and Billie Piper's Rose Tyler as The Moment.
However, one of the big moments came from Tom Baker playing 'The Curator' - who may or may not be the actual incarnation of the Doctor that he played himself all those years ago.
Moffat was pressed on that particular scene in a new interview and whether he would give more detail on who exactly The Curator was.
"Well, no, I think it was clear enough!" the showrunner told TV Choice.
"Or as clear as it should be, which is, there's enough there to tell you if you choose to believe that's the future incarnation of the Doctor, who's reverted to look like Tom Baker.
"But maybe he's lying and he's not. However, there's another perfectly adequate answer as to who the curator is.
"You could say it's the Moment [a sentient Time Lord weapon that can take different physical forms], because it originally was.
"Originally, I'd written the script with Billie Piper [who played the Moment] coming back, because she sort of disappears in the story.
"But when we thought we could get Tom Baker, I put him in. So that could be the Moment, just deciding to talk to the Doctor through this appearance."
So what was his guess as to what it was all about?
"I do think of it as, in the distant, distant future, long after Jodie [Whittaker] and long after we're all dead, the Doctor settles down and chooses a different incarnation per day to revisit," Moffat added.
"I like that idea."
Doctor Who will return with 'Twice Upon a Time', which airs on BBC One on Christmas Day at 5.30pm.
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