Planet of the Spiders - S11-E5
Revealing mistake: In episode one, when a psychic wind is blowing everything all over the Doctor's lab, look for the hatstand standing steady as a rock.
Planet of the Spiders - S11-E5
Revealing mistake: A bad CSO match up occurs in episode one, when Clegg is making the breakfast tray float across the room. The Brigadier is looking at a point some distance from the CSO'd tray.
Destiny of the Daleks - S17-E1
Revealing mistake: In episode one, when the Doctor and his companion hear rumbling and the ground moves beneath their feet, when they step away you can see that they are standing on different ground than before, and it's not shaking. (00:08:00)
Revenge of the Cybermen - S12-E5
Revealing mistake: At the climax of episode four, the Beacon plunges close to Voga and orbits very fast before the Doctor manages to break free. The planetscape that appears on the screen is quite obviously a revolving drum with bits of clay on it.
The Monster of Peladon - S11-E4
Revealing mistake: The mines are fairly obvious set constructions. The floor is flat with some sand thrown on. In addition, gaps can occasionally be seen between the floor and the walls or the floor and boulders.
Earthshock - S19-E6
Revealing mistake: Just before the Cyberman fires on the console, you can see Adric trying to keep as far away from it as possible before it explodes. (01:35:05)
Revealing mistake: How did Rubeish's glasses manage to improve his chronic shortsightedness when they are obviously plain lenses?
The Monster of Peladon - S11-E4
Revealing mistake: In the climactic fight at the end of episode four, the face of the Doctor's stunt double can be seen.
The Monster of Peladon - S11-E4
Revealing mistake: Near the end of episode six, when Aggedor is falling dead to the ground, the clothes of the man inside the costume can be briefly seen in a gap between Aggedor's leg and foot.
Revealing mistake: The footage of Kroll eating Harg is obviously reversed, as evidenced by the fact that the smoke from the pipe is heading into it, whereas in every other shot it's flowing out of it. (00:23:00)
Revealing mistake: Episode 6, while in the barn Von Weich asks Moor (played by David Troughton, son of Patrick, who plays The Doctor) to retrieve the monocle in his pocket. Then, when Von Weich continues with his plan, in his closeups we can see a vertical piece of mesh tape over the actor's right eye. (00:13:05)
Revealing mistake: When Noah bangs his green arm down, in a close-up you can tell that the arm has green bubble wrap around it. (00:02:30)
Revealing mistake: In episode 1 when the Doctor, Ian, Barbara, and Vicky leave the TARDIS, wheels are visible which move the prop around. There is also no back to the prop.
Revealing mistake: One of the stones wobbles when a crow lands on it in episode one.
Underworld - S15-E5
Revealing mistake: The pacifier devise is obviously a stage lamp.
Revealing mistake: In episode two, when Leela and Mandrell are arguing about raiding the Correction Center, the camera bumps against something.
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.
Revealing mistake: During the whole story, Tom Baker is struggling not to laugh at Tryst's completely made-up accent.
Destiny of the Daleks - S17-E1
Revealing mistake: The seam between the actor's real face and the Davros mask is very obvious, especially on the upper lip.
Answer: In 'The Five Doctors', three separate Cyberleaders are definitely used. So it's likely that Cyberleaders are like unit commanders, of which a fair-sized army might have several.
Daria Sigma