Originally, writer
Douglas Adams presented a wholly different idea for the season's six-part finale, involving the Doctor's retirement from adventuring. Facing resistance from producer
Graham Williams, Adams chose to avoid work on a replacement, under the expectation that time pressures would eventually force the producer's hand and allow his idea to be used. Ultimately, however, Williams forced Adams to conceive a new story as a last-minute replacement, which became
Shada. Under the original remit, Williams intended the story as a discussion about the death penalty, specifically how a civilisation like the Time Lords would deal with the issue and treat its prisoners. As composed by Adams, the story was scheduled to span six 25-minute episodes. Location filming in
Cambridge and the first of three studio sessions at
BBC Television Centre were completed as scheduled; After the production halt, Adams expressed a low opinion of the script and was content to let it remain obscure, turning down offers to adapt the story in various forms. He once claimed that when he had signed the contract allowing the script's 1992 release (accompanying the serial's
VHS reconstruction), it had been amongst a pile of papers sent over by his agent, and that he was unaware of what he was agreeing to. In 1983, footage from
Shada was used in "
The Five Doctors", the 20th Anniversary special.
Tom Baker, the fourth actor to play the Doctor, had declined to appear in the special, and the plot was reworked to explain the events in the scenes.
Cast notes Denis Carey was subsequently cast as the
eponymous Keeper in Tom Baker's penultimate story,
The Keeper of Traken (1981), and also appeared as the Borad's
avatar in
Timelash (1985). ==Reconstruction==