Plot hole: When the airlock door is opening at the end of the final episode, the Cyberman is the only one who appears to be affected by the air rushing out. Although 'rushing out' is probably overstating the speed of the 'explosive decompression'. It's not so much an explosion as a gentle breeze...
Plot hole: After the Doctor and Leela's clones fade, the camera pans to show Leela's knife. But since the knife was created in the cloning process, it should have faded out with Leela, the Doctor and their other personal items.
Plot hole: Oscar really does keep a clean restaurant. Even after Shockeye has stabbed him with a knife, the knife is clean, with no unsightly blood to be seen.
Plot hole: Why doesn't Lowe simply shoot Leela the second her back is turned? Moreover, why does he take them to get medical help? It's made clear that the virus has everything it needs on Titan.
Earthshock - S19-E6
Plot hole: The freighter traveling back in time makes no sense. According to Adric, the Cybermen's computer is responsible, yet the Cybermen possess no such technology; their machine's task was simply to navigate the freighter towards Earth. The idea that time travel could happen by accident is also absurd. (01:30:05)
Destiny of the Daleks - S17-E1
Plot hole: The Daleks spend a lot of time and effort mining down to where Davros is, despite the fact that there is a window on that level and Davros is on the ground floor.
Plot hole: Jo is surprisingly skeptical about the TARDIS being able to move, considering she saw it dematerialise in the last episode.
Plot hole: The Bandrils not only know of the Time Lords but are capable of connecting to them, yet the Bandril are barely capable of space travel and can't produce their own food. So, the Bandrils are not very technologically advanced it seems, so why do they have ties with the High Council of the Time Lords? And how does either party benefit from such an association?
Plot hole: It is highly unlikely that the discovery of a dead down-and-out's body in an empty warehouse would be reported in a national newspaper, especially as the discovery had to have been made when the newspapers were already being printed.
Plot hole: After Romana and the Doctor hide in the relic room, the Captain enters, then bends down to inspect the door that conceals the Shrivenzale. Unfortunately, the actor turns to his right when he does so, which make it rather odd that he doesn't see the white-clad Time Lady standing right in front of him.
Plot hole: Palmerdale and the others hear someone on the stairs. Skinsale opens the door and, despite Reuben being right in front of him, looks downstairs and calls out to the Doctor before turning and suddenly spotting the lumbering keeper.
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.
Plot hole: 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?).
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?
Plot hole: We twice see a map of how far the ice is away from the house, once in the first episode, and later in episode five. The ice has moved most of the way across the map in this time, and the distance it has moved is stated to be a 100 metres. This would place it only 20 metres from the base. The problem with the distance is that it takes Penley quite a while to get the injured Jamie to the base, including a stretch across open ground. Also, The Ice Warriors weapon targeter suggests the base is as much as two kilometres away. So just how far away is the ice; 20 metres, 2 kilometers...or somewhere in between?
Plot hole: Mr. Fibuli reports that the aircar the Doctor tried to steal is immobilized. Yet somehow, K-9 is able to activate it.
Plot hole: Peri goes to a fair bit of trouble to bolt the door on the bath house when rescuing the Doctor. When the Rani and the Master arrive, they simply open the door. Now this, in itself, isn't a mistake, as the Master has a special gadget for opening locked/bolted doors, but both the Master and the Rani seem surprised that someone is in the bath house.
The Monster of Peladon - S11-E4
Plot hole: The temperature of the air being blown into the mines is controlled from the communications room when the Doctor needs to knock out The Ice Warriors. But conveniently, the ventilation system is controlled from the refinery when Eckersley needs to suffocate the miners.
Plot hole: In episode 4 of "The Curse of Fenric", the weather is supposed to change for the worse and become very stormy. The Doctor and Ace are seen to be sheltering under an umbrella from the torrential downpour. Yet the skies in the background are bright, blue and sunny...
Answer: It was never destroyed on-screen; it was intact at the end of the TV movie, and destroyed by the start of the 2005 series. It was destroyed in the novel "The Ancestor Cell," but in a completely different manner to what happened in the series.
DaveJB