The Doctor (Doctor Who) footage. Tom Baker did reappear, but as "the Curator", an ambiguously different character who he was not credited for playing. A voice actor, John Guilor, recorded a line of audio impersonating the First Doctor, for which he was credited as "Voice Over Artist". In other multi-Doctor stories, the multiple actors are all credited as "The Doctor", the exception being "The Three Doctors" (1972–73), which credited William Hartnell, Patrick Troughton and Jon Pertwee as "Doctor Who" as the 1972 serial preceded the practice of crediting the character as "The Doctor". In "Human Nature" (2007), the plot involves the Tenth Doctor altering
An Adventure in Space and Time was in the Season 21 serial "Frontios"; Mark Eden appeared as the title character in the Season 1 serial "Marco Polo"; Nicholas Briggs, who has voiced the Daleks since the series was revived in 2005, portrayed his own predecessor; and Brian Cox voiced the Elder Ood in "The End of Time". Jean Marsh and Anneke Wills, who both played companions to Hartnell's First Doctor also appeared during Verity Lambert's leaving party scene. The drama was watched by 2.71 million viewers in the UK. Rotten Tomatoes gave it a 95% approval rating based on 22 reviews, and an average score of