Continuity mistake: When the Count's henchmen come into the café to get the Doctor, Romana and Duggan, they usher them all out at gunpoint. When you see them in the location filming in Paris, Duggan's not there...but back at the Count's place (in the studio in London) he's reappeared.
Continuity mistake: In "The Ribos Operation", Romana stated that her age was 'nearly 140' (presumably Earth years, although this is never confirmed). However, in the later story "City of Death", Romana says that she is '125 years old'.
Continuity mistake: When the Doctor finds the vraxoin vial in episode 1, he puts it in his right coat pocket, from where it is then removed by Stott. However, at the end of episode 2, Costa's scanner finds vraxoin traces in the Doctor's LEFT coat pocket.
Continuity mistake: In this episode part of the TARDIS set was erected incorrectly, resulting in some of the roundels emerging from the wall rather than being indented into it. This is very visible in all the TARDIS 'console room' shots.
Continuity mistake: In episode 4, approximately 5 minutes from the end of the story, Soldeed is shot after he pulls the lever that sets the complex on overload, and then crumples to the ground dead beneath the lever. Then, after the Doctor and everyone else get out of the complex, we see a selection of shots taken inside the complex - one of which is the room with the lever that Soldeed pulled, except he's no longer there...
Continuity mistake: After Skagra demands the book from Professor Chronotis, as Skagra's sphere floats toward Chronotis he's wearing his eyeglasses, but then the Professor's eyeglasses vanish and reappear while his hands are raised.
Continuity mistake: During the animated portions of Shada's missing scenes, in numerous shots an illustrated character's clothing (buttons, scarf, etc) become flipped, sometimes even within the same shot. Example: when The Doctor goes to the physics lab and meets Clare Keightley, note her buttons and The Doctor's scarf.
Answer: TARDISes are generally available for properly authorised use on Gallifrey; they're not usually assigned to a particular Timelord on a long-term basis. The Doctor stole his when he left his homeworld.
Tailkinker ★