3. Shada
One of the most famous scrapped episodes in the history of the show, you might've heard the word "Shada" thrown around a bit, probably in relation to
The Five Doctors, as Tom Baker's refusal to appear meant that producers had to reuse footage from this incomplete Fourth Doctor story. Conceived by The Hitch-hiker's Guide to the Galaxy author Douglas Adams, Shada is a planetoid in which the Time Lords lock up those who have tried to conquer the universe; after supervillain Skagra reaises he needs to talk to one of the inmates, he heads to Earth to find Professor Chronotis, the only Time Lord who knows the location of Shada. The serial was postponed due to a strike and never resumed, but what if it had been completed? Would it be Tom Baker's defining story as the Doctor? Would
The Five Doctors have become
"The Four Doctors" instead? Various writers have tried to finish the story; it was completed in 1992 with linking narration from Baker, and in 2012, 'The Lodger' writer Gareth Roberts novelised the story. Craig Owens didn't appear, though.