The last recorded scene of the story (and Doctor Who (1963) as a whole) was the final scene between Mrs Pritchard and Gwendoline.
The Doctor asks who was it that said Earthmen never invite their ancestors round to dinner. This is a reference to The Hitchhiker's Guide to the Galaxy, which was written by former Doctor Who (1963) script editor Douglas Adams .
Though not the last to be shown, this was the last episode of Doctor Who (1963) to be made by the BBC.
One key scene was not completed due to time constraints, and featured Mackenzie encountering the night maids and Mrs Pritchard as they prepare to leave, whereupon one of the maids chases him with a machete. This explains why he is hurrying and muttering about Gabriel Chase being "a mad house" just prior to his death at Light's hands. Several more scenes were cut or trimmed in post-production due to the serial running overlength. These included Nimrod resigning his position, Light preventing Mackenzie from leaving Gabriel Chase by causing the door to become bolted, and material expanding on the spy devices Josiah has secreted in the upper observatory where the TARDIS materialises.
During the early stages of his development, Light was silent and had wings (which he used to smother the maid in episode three); the latter element was abandoned due to concerns that they could not be effectively realised.