The Talons of Weng-Chiang - S14-E6
Revealing mistake: There are *modern* power points, covered with masking tape, visible on the walls of Litefoot's laboratory. The story is set in the 1890s.
Revealing mistake: Near the end of episode one, the Doctor peers into a hopper and sees ore piling up inside. The image of the ore wobbles back and forth.
Revealing mistake: At the beginning of episode four, when the Doctor is surrounded by robots, we initially see SV7 with *blue* eyes. Clearly someone forgot to add the glowing red-eye CSO.
The Talons of Weng-Chiang - S14-E6
Audio problem: In episode five, when the Doctor and Leela are in the opium den, the Doctor's lips do not match his spoken dialogue.
Revealing mistake: In Episode 3, when Dask is cutting the wires, the second explosion happens too early.
Revealing mistake: At the climax, when the Doctor and Sarah are setting up the scarf trap, the Doctor bumps a rock, which wobbles.
Continuity mistake: When Leela attacks the guard near the computer complex in episode three, his gun goes flying down the hall. But she then picks it up right next to his body.
Continuity mistake: In episode four, when the Doctor is patching the communicator into the android's head, he takes off the communicator's top, yet it is back on a few seconds later.
Visible crew/equipment: When Leela bandages Toos' arm, a member of the crew is visible on the edge of the set.
The Talons of Weng-Chiang - S14-E6
Visible crew/equipment: The shadow of a boom mike is visible on the curtains near the stage in the final fight.
The Talons of Weng-Chiang - S14-E6
Visible crew/equipment: In episode six, when the Doctor and his friends are hiding behind the table and Mr. Sin is blasting it, look out for the pyrotechnic wire dangling from the underside of the table.
Continuity mistake: When Toos is being hunted by a robot, she shuts the door on its hand. When you see this scene from the inside of the room, the robot's hand is trapped at a different place to the next shot, which is from outside the room.
The Talons of Weng-Chiang - S14-E6
Factual error: The Doctor mentions at one point in the story that he had once been fishing in the River Fleet with the Venerable Bede. The Venerable Bede was a distinguished 7th century scholar, who lived his entire life at Jarrow, on Tyneside, and never at any time came to London.
The Talons of Weng-Chiang - S14-E6
Continuity mistake: When the Doctor smashes the crystal lattice on the floor, the deactivated Mr. Sin flinches.
Continuity mistake: When Uvanov captures Leela he says she has killed three people, but he only knows Chub and Cass are dead. Then Poul tells him about Kerril.
The Talons of Weng-Chiang - S14-E6
Revealing mistake: At various points in the series, Mr. Sin is obviously a dummy and not an actor. But the most obvious is during the last fight when Sin jumps the Doctor. After a struggle, cut to a forward angle and the Doctor grabs and throws an obvious dummy to the ground.
Revealing mistake: When the Doctor is trying to unlock Uvanov's cabin door, Leela goes to join him and grabs the edge of the metal railing, which bends badly and then goes back to its original shape.
The Talons of Weng-Chiang - S14-E6
Other mistake: When Li H'sen Chang makes his entrance at the Police Station in episode one he says "You seem remarkably well-informed, Doctor", despite the fact he has not been told the Doctor's name and no other character has referred to him as such.
Revealing mistake: When the Doctor and Leela are confined to the officer's quarters, look at Leela's eyes after she sits down; one of her brown contact lenses has fallen out, revealing her real blue eye.
The Masque of Mandragora - S14-E1
Continuity mistake: When the Doctor is explaining about the Mandragora Helix, his scarf goes from being over his shoulder, to behind his shoulder and back.
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