Continuity: At the end of episode two, when the sink is emptied, the plug is placed on the bench. In the reprise for episode three, the plug is put back in the sink (thus enabling the miniaturized travellers to escape).

Plot hole: The miniaturized TARDIS crew never interact with the other characters in this story, because, as the Doctor points out, the 'giants' will be unable to hear them, as their voices will be on a different wavelength. So why does the Doctor later suggest using the telephone to try to call for help?

Factual error: The Doctor states that the Daleks invaded Earth because it is the only planet with a magnetic core. In fact, every planet in the solar system has a magnetic core.

Other: Ian has completely forgotten the distinctive shape of a Dalek. It's only when the Dalek starts speaking that Ian says to the Doctor, "that voice". Yet later when they are at the saucer, he talks to the Doctor about the new back of the Dalek having a disk on them now.

Revealing: In the scene where Barbra, Jenny and Dortman are running through the deserted streets of London, in the very last shot, if you look to the left of the screen, you can see some people walking down the street.

Continuity: The paint on the Black Dalek changes between episode 2 and 3.

Visible crew/equipment: When the rebels attack the Dalek saucer, a Dalek asks what sector the prisoners were taken from,, and in the bottom left hand corner a giant boom mike comes into view.

Audio problem: When the Doctor says that what they're seeing now is the middle period of Dalek history, you can hear a metallic thing being dropped off screen.

Revealing: When a rebel throws a bomb from the second floor of the Dalek saucer, notice it explodes too early and in the wrong place.

Revealing: In episode 1, one of the windows on the Tardis is leaning in, but by the time we get to episode 6 it has managed to fix itself. Also when the bridge falls down you can see the poster through the gap, showing that there is no back to the Tardis.

Audio problem: In episode 2 you can hear the Black Dalek clear his throat before speaking.

Revealing: When Barbra is throwing her bombs, she grabs the window frame in front of her, which wobbles alarmingly.

Visible crew/equipment: Just before Dortman leaves to test out his bomb, he comes towards the camera. When he's doing this, look at the right side of the screen - you can see a crewmember's shadow. It can't be Barbra or Jenny because they then enter from the left.

Audio problem: When the Dalek says to give the Doctor and Ian the test, it cuts to the prison cell where you can hear a Dalek voice that gets cut off.

Visible crew/equipment: When the Doctor and Ian are talking about the discs on the Daleks' backs, you can see a female crew member behind the robomen, standing there and then walking off, and then another crewmember in a white shirt dart past the robomen.

Visible crew/equipment: As the two prisoners join the Doctor and Ian, the camera follows them and you can see the heliport set through the Dalek saucer.

Revealing: At the beginning, as the Doctor is standing in the TARDIS door, the cave wall can be seen through the TARDIS.

Factual error: Nero seems to be middle ages, but the historical Nero was 27 at the time Rome burned.

Factual error: The geographical references in this story are somewhat suspect. Assissium is the modern town of Assissi, some 70 miles north of Rome and the same distance east from the sea. The Great Fire of Rome took place in July 64AD.

Other: In the end part of this story, in the large spiders den, you can see the string supporting it.