Brod was one of the few remaining normal humans on an devastated Earth in an alternate timeline in the year 5000. When the Third Doctor visited this timeline, Brod knew of him from history books in what remained of the British Museum. Brod asked that he use the TARDIS to change history and prevent his world from coming to pass. He travelled with the Doctor to 1872 to try to convince Professor Theodore Cassells to not publish his work, which had led to the global war that devastated the planet. When Cassells drowned with the crew of the Marie Celeste, Brod vanished, his timeline erased. (COMIC: A Stitch in Time)
The Third Doctor's stage play companions are difficult to assert with certainty as being particularly his companions, because the play in which they appeared was performed with several different actors in the role of the Doctor. His "single-adventure" companions in comics occupied a very similar narrative space to the single-adventure companions of the Tenth Doctor's era. They all travelled in the TARDIS and in every way acted as a companion within the storyline. Though this Doctor appeared in prose stories, he never had a companion to originate in that medium.
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