Other mistake: In episode 3, watch the scene where the co-pilot is shooting; you can see his pants rip straight down the seam at the back - which unfortunately happens to be the part of him facing the camera at the time. He then wanders around for most of the rest of the episode with the tear in his pants plainly visible.
Plot hole: When Della gets shot in the face in episode four, she clutches her stomach. (What is even more remarkable about this error is that this keeps happening over and over again: someone gets shot and falls to the ground, clutching their stomachs, regardless of where they have actually been shot. See the error in Season 14's 'The Deadly Assassin' for an example of the SAME error occurring).
Revealing mistake: Geoffrey Hinsliff (playing Fisk) accidentally refers to Tryst as "Fisk" at one point.
Continuity mistake: In "The Ribos Operation", Romana stated that her age was 'nearly 140' (presumably Earth years, although this is never confirmed). However, in the later story "City of Death", Romana says that she is '125 years old'.
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)
Continuity mistake: In episode 4, approximately 5 minutes from the end of the story, Soldeed is shot after he pulls the lever that sets the complex on overload, and then crumples to the ground dead beneath the lever. Then, after the Doctor and everyone else get out of the complex, we see a selection of shots taken inside the complex - one of which is the room with the lever that Soldeed pulled, except he's no longer there...
Continuity mistake: When the Doctor finds the vraxoin vial in episode 1, he puts it in his right coat pocket, from where it is then removed by Stott. However, at the end of episode 2, Costa's scanner finds vraxoin traces in the Doctor's LEFT coat pocket.
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.
Continuity mistake: During the animated portions of Shada's missing scenes, in numerous shots an illustrated character's clothing (buttons, scarf, etc) become flipped, sometimes even within the same shot. Example: when The Doctor goes to the physics lab and meets Clare Keightley, note her buttons and The Doctor's scarf.
Visible crew/equipment: After Chris exits the TARDIS with the medical kit, Romana places the collar around the Professor's neck. When Romana tells Chris that Chronotis, "Should be able to think with it," in the next closeup of Chris the moving boom mic is visible at the top of the screen, before he kneels down.
The Creature from the Pit - S17-E3
Plot hole: In part 2 it's brought up in conversation several times that all metal is rare on that planet. Handy exposition for the viewers, but it's in fact a really odd thing for the characters to say. The inhabitants aren't giving a tour of their planet (certainly not deliberately at any rate), so why would they state facts that have been well known to them all of their lives? It's a bit like meeting strangers and informing them that two thirds of the Earth are covered by oceans.
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