Theory:Doctor Who television discontinuity and plot holes/Ghost Light


 * After having been given considerable screen time in Episode One, Redvers' glowing snuffbox disappears from the plot. No reason is subsequently offered as to why Josiah would want to trap his non-expendable would-be assassin in a room with an exposed radioactive source.
 * Why does Josiah think that killing the Queen will mean that he takes over the Empire?
 * Because he's an alien who doesn't understand how the line of succession works. He's operating under the assumption that he can 'evolve' through natural selection to the top of the food chain.
 * It is also strongly implied that Josiah killed the previous owner of the house (Gwendeline's father, Mrs. Pritchard's husband) and hypnotised the remaining inhabitants of the house in order to seize control of it in the first place. So he just assumes that is the way power works. Even though this plot should have been the main focus of the story, the main plot in the televised version is Light threatening to reduce the Earth to a barron planet composed nothing but primordial soup.


 * Light is strongly opposed to the idea that any lifeform can change or evolve in any way, and yet it is implied Josiah's purpose is to be sent to the surface of a planet and evolve itself to become the planets dominant lifeform, so why would Light keep Josiah as a member of his crew and not just destroy him?
 * As the Doctor acidly remarks, Josiah and Control are not crewmembers but mere "cargo" fulfilling their function, which appears (at least in Josiah's case) to be mimicking the indigenous lifeforms of surveyed planets to aid Light in his cataloging. Josiah is merely fulfilling his function by mimicking the evolution of Terran life (which specifically annoys Light because it has rendered his life's work obsolete), and Light is at least fair enough not to shoot the messenger. Having said that, Josiah is afraid of Light, for the very good reason that his attempted mutiny was definitely not part of his function ...


 * It is not clear what species Light is, or where he is from, or how he came across such astonishing power. It is also unclear what species Control and Josiah are and how he came across them.
 * Given his age, his "angelic" resemblance, his immense powers, his amoral scientific interest in Earth, his buried flying saucer, and his fatal "imagination - lack of", he is more than slightly reminiscent of Azal. Possibly from an associated or rival faction of godlike entities. Still, there seems to have been a fair old crowd of Great Old Ones and assorted eldritch horrors competing to screw up the early evolution of humanity in the Whoniverse ... As for Josiah and Control, a being of Light's power could conceivably create, mutate, or enslave whatever operatives he needed to serve his purposes.
 * Just like Azal, Light also seems, despite his enormous power, to be in some ways less than an independent, sentient being- Light cannot comprehend things outside his 'programming' just as Azal's "instructions are precise". Perhaps they are both Daemons- Azal in demonic guise tests and assesses lifeforms adaptability to chaos and change, whilst Light in fallen angelic guise assesses and cataloguesl, and orders the forms of life as they are at the point of cataloguing- and just as Azal is concomitantly incapable of understanding a response anathema to natural selection- Jo being prepared to sacrifice herself for the sake of an alien for no purpose but altruism, similarly Light is incapable of understanding change.


 * In Episode Two, Rev. Matthews is rendered unconscious by what may be chloroform, during an argument about evolution with Josiah. Upon waking up Rev. Matthews continues the argument with Josiah and while eating a banana slowly transforms into a monkey. It is unclear how this was possible along with why the devolved Rev. Matthews freezes at 6 o'clock along with the other permenant inhabitants of the house.
 * In the novelization, it is stated that Josiah simply gets bored with him and has Gwendoline kill him very quickly, prior to sticking him in the display case (implied in the series with the "going to Java" line). Presumably the chloroform was a fatal dose. As for the devolution itself, the most likely explanation is that Josiah had used some of the technology stolen from Light's ship.


 * At the end of Episode One Ace discovers Josiah's husks which are under Control's influence and guidance. Control refers to Ace as "Ratkin", and no explaination is offered as to why. Ace brings it up a few times later but Control still offers no explaination. Perhaps there is an explaination in the novelisation.
 * Control has been in hibernation since the dawn of time. So it assumes Ace is an alien. "Ratkin" could just be its native word for "alien".

Ref: "Ratkin:" theory above could be right, but I believe both of the guards who say this to Ace were lizards, so for them Ace, a human mammal, would be ratkin - kin with a rat, also a mammal.