Continuity mistake: In episode 1, when the Doctor opens the garage doors with his 'door handle', note the two men in the background, the position of the car behind him and the white pillar. In the next shot, the men and pillar disappear and the car moves to a different spot. In the shot after that, the tanker truck is now parked in front of a pillar. You can see near the beginning of episode 3 that there are two entirely different buildings that the tanker had been filmed in front of. (00:14:25)
The Ambassadors of Death - S7-E3
Continuity mistake: There are a handful of similar continuity errors, but one that stands out in particular occurs at the end of Episode 1. The Doctor and Liz go into the lab and Taltalian steps out from behind the door wearing glasses and brandishing a gun. However, in the recap at the start of episode 2 he isn't wearing glasses and moves differently.
Continuity mistake: In episode three, the readout strip dangling from K-9's mouth shortens between when he shoots the infected crewman and shoot Leela.
Continuity mistake: The amount of dirt on the Doctor's face changes between the Bath House and the exterior filming.
The Caves of Androzani - S21-E6
Continuity mistake: When the Doctor and Peri first land on Androzani, mountains are seen in the background. They disappear when Peri picks up the silica. A couple of shots later, they're back. (This mistake was mentioned on the DVD commentary; the mountain effect was left out for financial reasons).
Remembrance of the Daleks - S25-E1
Continuity mistake: After the Special Weapons Dalek blows up the gate to Ratcliffe's warehouse, you can see that some of The Daleks were slightly damaged by the explosion. In all the following shots, they have been repaired.
Genesis of the Daleks - S12-E4
Continuity mistake: In episode 6, when the lead Dalek is saying 'Pity? I have no understanding of the word' the lights on the top of its dome stop working. They start working again in the following shot. (00:21:00)
The Sea Devils: Episode Two - S9-E10
Continuity mistake: In episodes 2 and 3, watch the clock on the wall in the Master's quarters. When the Master pulls a gun on the Doctor and the Doctor quickly pulls the door shut, the clock shows ten minutes to three. In the next episode, after the swordfight is over and the Doctor is being led out by the guards, the clock now shows approximately eight minutes after twelve.
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.
The Dalek Invasion of Earth - S2-E2
Continuity mistake: The paint on the Black Dalek changes between episode 2 and 3.
Continuity mistake: As the Master escapes from Axos, he kills the UNIT soldier standing guard outside, whose beret falls off as he slumps to the ground. Cut to the Master standing over the corpse, and the missing beret instantly replaces itself on the head of the corpse.
The Daemons - S8-E5
Continuity mistake: After completing the third summoning ritual, the Master turns towards the spot where Azal is about to appear. He has his arms lowered and Jo is stood to his left. In the next shot his arms are up, and Jo has moved to being in front of him.
Genesis of the Daleks - S12-E4
Continuity mistake: When Sarah falls from the scaffolding, a plank of wood saves her from death. Trouble is, she fell a foot from the outside of the scaffolding and most of the plank was inside the scaffolding, therefore her feet would have hit it and she could only have landed with her head pointing inwards. But when we see her, her head is pointing outwards. (00:01:25)
Continuity mistake: The rhyme the Doctor recites in episode 3 is different from the original rhyme heard in episode 1. (Apparently, the Doctor [William Hartnell] forgot his lines in episode 3, when he came to the point of reciting the rhyme. So he just improvised what he thought they were, rather than what had been scripted).
Continuity mistake: At one point in the story, the Doctor hurriedly types out a letter to leave for the Brigadier and Sarah Jane, and pins it to the TARDIS. Later when Sarah Jane reads the note, you can see it's been handwritten.
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?).
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.
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.
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