The Doctor (Seven Keys to Doomsday)
From Tardis Wiki, the free Doctor Who reference
One incarnation of the Doctor travelled with his companions Jenny and Jimmy to the planet Karn, to prevent the Daleks from gaining the Crystal of All Power. He resembled a middle-aged man, with a hoarse voice. (AUDIO: Seven Keys to Doomsday)
Behind the scenes
This incarnation of the Doctor originated in the stage play Doctor Who and the Daleks in Seven Keys to Doomsday, in which he was implied to have followed Jon Pertwee's Third Doctor. The stage play version of this character, therefore, was the Fourth Doctor before Tom Baker was cast as the true Fourth Doctor for television.
In the audio adaptation, an incarnation played by Nicholas Briggs preceded him.
