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.
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
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
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.
Continuity mistake: Susan's socks disappear during the opening credits.
Marco Polo - S1-E4
Continuity mistake: The caption slide at the end of episode two reads: 'Next Episode: The Cave of Five Hundred Eyes'. While the title slide comes up at the start of episode 3, it simply says "Five Hundred Eyes".
Suggested correction: The original episode survives only as audio, so this mistake, if correct, must apply to one of the reconstructed versions (either telesnaps or animation), which probably therefore needs specifying.
Continuity mistake: In episode one, Barbara activates her travel dial only seconds before the others. But in episode two, she's been at Morphoton for quite some time - long enough to change clothes, pick fabrics and get food.
The Dalek Invasion of Earth - S2-E2
Continuity mistake: The paint on the Black Dalek changes between episode 2 and 3.
Continuity mistake: In episode one, Vicki passes her hand through a museum display, making the point that the crew cannot interact with their environment. A moment later, she bumps into a statue, making it wobble.
Continuity mistake: When Frankenstein's Monster begins chasing The Daleks, he's wrapped in bandages. When he catches The Daleks in the room with the TARDIS, he's suddenly wearing a suit.
Continuity mistake: When the Doctor and Ian encounter the Frankenstein monster in episode four, you can see a Dalek behind them, even though it's long before The Daleks arrive in this time zone.
Continuity mistake: In episode four, when the Doctor and Ian return to Frankenstein's lab, the monster is lying on the table in the opposite direction from when they left.
Continuity mistake: Towards the end of episode 2 it's nighttime, but when Ian and the Doctor lure the Dalek over from the TARDIS, and when it falls, it's daylight.
The Daleks' Master Plan - S3-E4
Continuity mistake: In the cliffhanger to episode 1 of this story, as The Daleks approached the TARDIS, the TARDIS door was open. At the beginning of episode 2, seconds after the cliffhanger moment in 1, the door is suddenly closed. (00:01:00 - 00:02:00)
Continuity mistake: The six-shooters, in the climactic gunfight, fire off a lot more than six shots without reloading.
Continuity mistake: The rhyme the Doctor recites in episode 3 is different from the original rhyme heard in episode 1. (Apparently, the Doctor [William Hartnell] forgot his lines in episode 3, when he came to the point of reciting the rhyme. So he just improvised what he thought they were, rather than what had been scripted).
Continuity mistake: The dialogue between Cutler and the technician at that beginning of episode 3 is slightly from that which closes episode 2.
Continuity mistake: In Episode 1, the TARDIS crew pass out from the change in pressure as they descend into the Earth. However, at the end of episode four, they climb out on foot and suffer no ill effects.
The Evil of the Daleks - S4-E9
Continuity mistake: (Animated version). Waterfield puts down the photo of the Doctor on his desk but the next time we see his desk the photo is no longer there and then later it's back on the desk again, without Waterfield having moved it.
Continuity mistake: At the start of the story (the beginning of episode 1) the TARDIS materialises on its side, but at the end of the story (the end of episode 6) the TARDIS dematerialises right side up.