Plot hole: It is never explained why so much of the story takes place in England. All of the equipment for Sutekh's rocket comes from his tomb and could just as easily - probably more easily - have been set up right there in Egypt. And at the end, instead of just walking out of his tomb, he takes the spatial corridor to England just so he can get caught in the Doctor's trap.
The Trial of a Time Lord 5-8 (aka Mindwarp) - S23-E2
Continuity mistake: When Kiv wakes up in Peri's body, (s)he orders Crozier to kill the body Kiv was using before. Crozier responds that it's already dead, but in the previous shot the old body could be seen breathing.
Continuity mistake: The sketch of Romana is different when it's seen outside the café from the one seen inside the café (and just who's doing the sketch, and why?).
The Dalek Invasion of Earth - S2-E2
Revealing mistake: When Barbara, Jenny and Dortman are running through the deserted streets of London, in the very last shot, if you look to the left of the screen, you can see some people walking down the street.
Revealing mistake: When SV7 comes into Taren Capel's workshop, its usual eyes are missing - only black discs are visible (later in the scene, these are overlaid with the red speckled pattern to show the robot being reprogrammed).
Continuity mistake: When Frankenstein's Monster begins chasing The Daleks, he's wrapped in bandages. When he catches The Daleks in the room with the TARDIS, he's suddenly wearing a suit.
Continuity mistake: In episode one, Vicki passes her hand through a museum display, making the point that the crew cannot interact with their environment. A moment later, she bumps into a statue, making it wobble.
Visible crew/equipment: As the Doctor is watching Will emerge from the priest-hole, look over his shoulder at the far corner. Someone or something appears to be moving in the shadows there.
The Caves of Androzani - S21-E6
Visible crew/equipment: The boom mike is visible at the top of the screen when one of Jek's androids is handing spectrox to the mercenaries. The shadow of the boom pole is also visible on the roof beam.
Other mistake: In episode two, when Poul enters the room where Uvanov and D84 are holding Leela, the body of Cass breathes.
The Masque of Mandragora - S14-E1
Factual error: Giuliano explains to Sarah that he thinks the world is round as though this were radical. But this was the common belief throughout the late Middle Ages. The argument was about how big the Earth was and the ignorance about the existence of a continent between Europe and Asia.
Invasion of the Dinosaurs - S11-E2
Visible crew/equipment: In episode 4, when the Doctor is in the Whomobile, a dark cylindrical object passes in front of the camera in the foreground. It's not something of the Doctor's, as his hands are inside the vehicle.
Invasion of the Dinosaurs - S11-E2
Continuity mistake: In episode 3, Sarah is hit on the head by debris knocked loose by the escaping dinosaur. It hits her on the back of her head or shoulders - but the later bruises and scratches are on her forehead.
Audio problem: In the first scene with the Dalek Supreme, the lights on its dome are way out of synch with its speech.
Revealing mistake: The "American" accents in this episode are all over the map and frequently inconsistent within the same scene.
Deliberate mistake: One major mishap occurred just prior to editing, when a videotape containing various close-up and insert shots was accidentally wiped. At that point, there was no way that the director (Nicholas Mallett) could go back and rerecord the material, and so he was forced to work without it. This meant using footage that would usually have been discarded or replaced. The 'give aways' that reveal that Mallet had to work around the problems of the missing footage are (a) the lack of any close-ups of any of the actors in the final 10 minutes of episode 4, and (b) the continuity error involving the flames in the laboratory for the same period...the flames go from low to high and back to low from shot to shot.
Revealing mistake: In episode 2, when Scaroth locks the Doctor, Romana and Duggan in the basement dungeon, and Duggan lights the lamp, notice that Tom Baker is standing between that lamp and the actual stage light used to brighten the scene. So, as the lamp is lit in front of him, Tom Baker's BACK (and not his front) glows bright under the increased illumination.
The Trial of a Time Lord 13-14 (aka The Ultimate Foe) - S23-E4
Audio problem: All of the scenes of the trial have some sort of sound problems. Among other things, sound bites from earlier on appear from seemingly nowhere, and, if you listen carefully, you can hear someone calling out the cue "Take 6", which should have been edited out quite easily, but wasn't.
Continuity mistake: Near the end of episode 4 of "The Curse of Fenric", when Ace and the Doctor run out of the exploding bunker, the Doctor stumbles in the mud and puts his hand out to stop himself falling, getting mud all over it. The Doctor even stops to look at his muddied hand, in an almost symbolic gesture. Then the director goes in for the close-ups with the Doctor and Ace, and when the Doctor puts his hand up to rub Ace's nose (same hand), it's perfectly clean.
Plot hole: The linchpin of the plot makes no sense whatsoever. In an effort to diffuse international tension, the superpowers would allow Britain to publish the codes that would allow anyone in the world to launch their nuclear missiles? And then, after going through the drama of not one but two countdowns, it's revealed that the superpowers can just activate safety over-rides to prevent the launch. So how in Hades did the SRS have any threat whatsoever to wield over them and issue their demands?
Chosen answer: No, it was the result of the Cybermen's draining Earth of energy to their world, that also affected the Doctor, draining his energy as well, causing him to regenerate.
Also In the episode it's said that his body was wearing thin.
Dan23