The Nightmare Fair (unproduced TV story)
From Tardis Wiki, the free Doctor Who reference
The Nightmare Fair was an unproduced TV story for the original Season 23, before it was put on hiatus. It was later adulterated into the Telos novel of the name name, and that was adapted into an audio adventure.
Plot set-up
The story would have continued strait from Revelation of the Daleks, with the Doctor's destination for Peri being "Blackpool."
The idea had come to John-Nathan Turner to set the story in Blackpool when Colin Baker had opened a ride there called "Space Mountain." The story would also have been set partially there, with the Celestial Toymaker making strange things happen.