100,000 BC - S1-E1
Revealing mistake: Susan is supposed to be running through a forest. It is painfully obvious that, in fact, she is simply running on the spot against a back-projected film, and the branches that hit her are simply studio stagehands, hiding just out of shot, hitting the actress with twigs.
100,000 BC - S1-E1
Continuity mistake: When Ian and Barbara enter the TARDIS for the first time, Susan operates the door switch. Later on, when the Doctor electrocutes Ian, he uses the exact same switch.
100,000 BC - S1-E1
Character mistake: When Ian is trying to escape from the TARDIS in episode 1, he says, "He closed the door from over there, I saw him." It was in fact Susan who closed the door.
100,000 BC - S1-E1
Visible crew/equipment: The boom mic makes an quick appearance about 18 minutes into episode one. It is in the upper left corner when the camera switches from a close up of the Doctor and Susan to a medium shot of all four characters.
The Daleks - S1-E2
Visible crew/equipment: About 90 seconds into Episode Two, the shadow of the boom mic crosses Ian's face. (00:01:29)
The Daleks - S1-E2
Revealing mistake: In episode one, when Ian notices the breeze, a wide shot of the forest shows the background dropcloth is moving. (00:02:10)
The Daleks - S1-E2
Revealing mistake: The Dalek that Ian hides from in Episode Seven has a bad castor. The flopping of one of its wheels is audible. (00:08:20)
The Daleks - S1-E2
Visible crew/equipment: The boom mic shadow makes an apperance in Episode Two, moving across the console as the Doctor suggests abandoning Barbara.
The Daleks - S1-E2
Revealing mistake: In episode six, Ian helps Barbara get a grip on the rock and a piece of the polystyrene pops off in his hand.
The Daleks - S1-E2
Continuity mistake: In episode three, Temossus claims the Thals have been travelling for four years. But in episode five, Ganatus claims it is one year.
The Daleks - S1-E2
Revealing mistake: The supposedly heavy statue Ian drops down the lift to destroy the pursuing Dalek in episode four wobbles when he first touches it.
The Daleks - S1-E2
Revealing mistake: Toward the end of episode two, when Susan opens the TARDIS doors, the console wobbles.
The Daleks - S1-E2
Revealing mistake: In the Dalek city, it is unfortunately obvious that the "tunnels" behind the actors are just photographic blow-ups, as you can see the bottom of the wall meeting with the floor.
The Daleks - S1-E2
Revealing mistake: There are numerous scenes where the background Daleks are blown-up photographs. The most obvious is in episode five when The Daleks are discussing the radiation drugs.
The Daleks - S1-E2
Continuity mistake: The Dalek the crew ambush in episode three has a magnetic block in its sucker and, after the attack, a mud-covered eyestalk. At the beginning of episode four, the eye-stalk is visibly clear of mud, yet is later seen plastered with mud once more.
The Daleks - S1-E2
Revealing mistake: When the Thals are using sunlight to blind the Dalek cameras in Episode Six, wide shots of the Dalek city show it moving back and forth from bad matte combination.
The Daleks - S1-E2
Visible crew/equipment: Toward the end of episode one, when Ian is wondering where Barbara is, the shadow of a boom mic moves over the door behind him.
The Daleks - S1-E2
Plot hole: Why does The Daleks' prison have beds? The Daleks don't need them and clearly state that they have no idea what the Thals look like, speculating that they are "horribly mutated".
The Daleks - S1-E2
Continuity mistake: The Doctor removes his coat and it's left in the prison cell but in the brief shot of the Doctor and Barbara pushing Dalek Ian, the Doctor is inexplicably wearing his coat again.
Revealing mistake: You can see the studio floor in the "white void" outside the TARDIS door in early shots during episode one of this story.
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