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.
The Ambassadors of Death - S7-E3
Continuity mistake: Taltalian's French accent mysteriously gives way to an English one in some shots, most notably on location, e.g. when he catches an escaping Liz and says "Get in Miss Shaw".
The Ambassadors of Death - S7-E3
Continuity mistake: In episode 4 a UNIT sentry (Max Falkner) is seen shooting at one of the ambassadors when he is killed, but in episode 6 he is alive and well and is seen again in the 1976 story "The Android Invasion" , this time as a corporal.
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.
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