Logopolis was the Doctor Who episode where Tom Baker’s fourth Doctor regenerated into Peter Davison’s incarnation. It ended Baker’s unrivaled seven year run in the magical blue Police Box.
I managed to catch a repeat of Logopolis on Sci-Fi this week (I’d recorded it a while ago), and most of the plot is easy to follow. However, throughout the entire episode, a white figure observes everything that’s happening and is present whether the [[TARDIS (Doctor Who)|TARDIS]] is on Earth or on Logopolis. The white man is revealed later to be the person who flies the TARDIS off while The Doctor remains in Logopolis.
Finally, we’re told that the white man is a version of The Doctor, and whenever Baker’s regeneration begins, he morphs briefly into the white man before changing into his fifth incarnation.
So, what’s up here? To my eyes, the white man is some kind of intermediary entity, something between incarnations. So, does he exist in the future? Does he use the TARDIS to travel to the points where the Fourth Doctor was in order to forewarn him? I don’t know, it’s all a bit vague. Any suggestions?