The Nightmare Fair is a story originally written for the 1986 season of Doctor Who, but never filmed. A novelization based on the script was published in 1989 by Target Books, as the first volume of its Missing Episodes series. The script and novelisation was written by former series producer Graham Williams, and would have been directed by Matthew Robinson had it gone to air. It is the first novel-length text featuring The Doctor not to be based upon a previously transmitted production, although being a novelization it is not strictly speaking an "original" novel; the first such book appeared in 1991.
An audio play closely based on Williams' script was released in May 2003, with profits going to the charity Sense. For this adaptation, the Sixth Doctor was played by Steve Hill, and Peri by Jennifer Adams Kelley.
A further audio adaption, by Big Finish, was released in 2009, adapted by John Ainsworth, featuring Colin Baker as the Sixth Doctor.