Written by Ted Lewis, and also known as "The Doppelgängers", The search for the fourth segment of the Key to Time takes the Doctor and Romana to Nottingham where they meet Robin Hood and discover that the alleged hero is actually a blackhearted villain. The scripts for the first two episodes of the four-part fourth serial of the season were delivered to the production office on 28 April 1978. Although a third script arrived on 12 May 1978, Lewis turning up inebriated to a meeting with Graham Williams and Anthony Read and the unsuitability of the submitted material meant the story was dropped and replaced by David Fisher's "The Androids of Tara", which deliberately adopted the same swashbuckling genre as Lewis' storyline.