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
The Doctor (Doctor Who) the regions" with a Scottish one, and so asked Tennant to affect the same accent he used for the earlier BBC period drama "Casanova". In contrast, Peter Capaldi was explicitly allowed to continue using his native Scottish accent as the Twelfth Doctor. In the Big Finish audio adventure "The Sirens of Time", the captain aboard a German U-boat assumes he is English because of the way he pronounces his words: "So, you speak German ... but you speak it like an English gentleman." The Doctor's clothing has been equally distinctive, from the distinguished Edwardian suits of the First Doctor to