The first time the idea of a special video-only anniversary special was mooted was in a memo Nathan-Turner wrote to Head of Video Production Penny Mills on 18 February 1992. With Tom Baker not averse to appearing should conditions be met, serious thought was given to an original production and there was a meeting in June 1992 to discuss the concept of the special; by 21 July 1992 writer Adrian Rigelsford (later joined by Joanna McCaul) had completed an initial outline for the story entitled "Timeflyers". Shortly afterwards the project was given the cover name "The Environment Roadshow". A production office was opened for the project in the first week of September 1992 with shooting planned for January–February 1993. The script was sent to Peter Cregeen on 22 March 1993, indicating at the same time that Graeme Harper was being looked at as a potential director for the special. However, issues with budget plagued the production and shooting slipped to taking place November–December 1993 with a final delivery date of 14 March 1994. Around mid-May Cregeen indicated that he'd like to see the special broadcast on the BBC in November 1993. By the end of May 1993, the project was now being referred to as "The Dark Dimension" before a new working title of "Lost in the Dark Dimension" was settled on. Harper was contracted as the director of the special in June 1993 and intended Rik Mayall to play the part of the villain, Hawkspur. What was hoped to be the final shooting script was completed on 21 June 1993 and with the production now aimed for broadcast than a direct-to-video release, Alan Yentob gave the special the green light with the plan to have the completed project delivered by 27 November 1993 but by the start of July 1993, budget issues continued to plague the production and on 9 July 1993 the project was officially cancelled. With the project sunk, the thirtieth anniversary was instead celebrated with the light-hearted Children in Need charity special "Dimensions in Time" and the documentary "30 Years in the TARDIS". The BBC press release had hinted at the plot with the following: