The scene in which a half-changed Noah confronts the doctor and Vira was originally longer. Noah told Vira he was in torment and begged her to kill her. However, the Doctor closed the bulkhead when Vira couldn't decide. This explains the rather clumsy editing in which Noah drops the gun at Vira's feet and the shutter is suddenly closed. Contrary to urban legend, this scene did not involve Noah's head splitting open. That only occurred in the novelization.
Humanity in the future is divided into functional groups, like insects, but Rogin wakes up as a fully-fledged Holmes wideboy.
Vira: Well, suffocation is not the most unpleasant way to go.
The Doctor: I know it's irrational, but human beings are quite my favourite species.