Other Mistake: The back of the Cyberman's head is loose.
Equipment Visible: After entering the Miniscope, the Doctor helps Jo over a piece of equipment. As they walk off, the shadow of the boom mike moves over a white piece of the set in the upper right part of the screen.
Continuity: The TARDIS doors are open when the Doctor steps out but instantly close when the giant hand reaches for it.
The Doctor [ pointing to a piece of machinery ] You see this? You know what that is? That's a bearing housing for one of the ventilator shafts.
Jo: Oh, good. Knowing makes me feel so much better.
The Doctor: Well, I thought it might.
The Doctor: Jo, get up.
Jo: Not yet. I'm only half-cooked.
Vorg's specimens include Drashigs, Ogrons (he mentions that they are slaves of the Daleks) and a Cyberman (using a costume from Season 6's The Invasion).
An earlier version of this episode that, with a full repeat of the sequence on Inter Minor from
This alternative version of Episode Two was the one used on the video release. The DVD release has the broadcast version of the episode, with the new Delaware theme and the extra scenes included as special features on the disc.
John L. Sullivan: The Doctor claims to have taken boxing lessons from this boxing champion of the 1880s.
The Drashig monsters' name is an anagram of dishrag.