Theory:Doctor Who television discontinuity and plot holes/Terror of the Zygons


 * The Brigadier is heard speaking to a female Prime Minister, though cannot take place in the future Thatcher years as the Brigadier had retired by then. (TV: Mawdryn Undead)
 * In the DVD commentary for Frontier in Space, Terrance Dicks says that the reference to the PM as female as an ad-lib by Nicholas Courtney; the BBC's website states this Prime Minister to be Shirley Williams, who was never a Labour Party leader in real life but was a notable member of the Cabinet.


 * Would destroying an energy conference, even if all of the world's major leaders were present, really cause the kind of havoc the Zygons need to pave the way for an invasion?
 * This was only to be the first of several such attacks. Also, it would definitely provide a distraction.


 * Broton's explanation at the end of episode three that the destruction of the various oil rigs was only a 'trial of strength' for the Skarasen seems a little unconvincing. Surely they could have come up with a less elaborate plan to test the readiness of their monster; one that wouldn't draw so much attention?
 * Broton's explanation was only a ruse so-as not to give away their real plans to UNIT. It was the destruction of the oil rigs which triggered the emergency energy conference which the Zygons were planning to attack all along.
 * However, in episode 4 the duke describes the conference as the "Fourth International Energy Conference", suggesting a scheduled event rather than an emergency meeting. Nonetheless, both the conference attack and the destruction of the rigs suggest a broad agenda of sabotaging human infrastructure, which would aid the Zygons' purposes.


 * What were the Zygon's plans prior to hearing about the destruction of their home world? They seem to have been hanging around under Loch Ness for centuries.
 * They did not have enough fuel to return home so they just intended to stay hidden for the rest of their lives. However, once they'd heard that their people had become refugees, they knew they had to seize control of the Earth and sprung into action.


 * In episode 4, The Doctor says "What are you going to do with it(earth) when you've got it? Isn't it a bit large for just about six of you?". But only three zygons were alive at that time.