This was the last story to be produced under the aegis of "Doctor Who" creator Sydney Newman, who left his position as Head of Drama at the BBC upon the expiration of his contract at the end of 1967. The four key production roles for this story were all taken by men heavily involved in the development of Doctor Who. Author David Whitaker had been the show's first script editor; Barry Letts, directing the show for the first time, later became the show's producer (for the majority of the Jon Pertwee era), executive producer, and occasional script writer; script editor Peter Bryant became the show's producer from the next story; Innes Lloyd was the show's current producer, but left after this story.