Roots: 'With empowerment comes responsibility' - a misquote of Amazing Fantasy #15. 'becoming the world in which humans lived and moved and had their television' on page 217 is an allusion to Acts 17.28, itself a quote from Epimenides. There is a brief reference to the guns of Navarone - a reference to the 1961 movie The Guns of Navarone, based on a book of the same name.
Goofs: How does the Doctor know that Sarah is at Hubway?
If the Doctor can see the Great Hall from the Kitchen surely he can be seen in the Kitchen from the Great Hall. [Maybe the Voracians are stupid enough to not check if there's anybody else in the building.]
How can the Doctor communicate with computer programs in English?
If Johanna can find the Doctor by using light sensors why does she not use that information herself, rather than just programming local systems to react?
Did the Doctor really have time to convince the network that locations within Hubway are nodes of the Highway?
If the Voracians can stop Sarah from running outside how can she escape them after being dragged inside?
On page 294, the Doctor's version of Voractyll describes himself as "flexible and adaptive." But this undercuts the whole argument he has been sent out to make to the other Voractyll - that machines are inferior to organic life because they aren't flexible and adaptive.
Dialogue Disasters: We're dicing with death on the information superhighway to hell.'
Dialogue Triumphs: 'The only thing worse than being shot is being shot in the rain.'
'You can find any information or data on the highway - from the Bible to pornography, from serious discussions of politics to the speeches of Ronald Reagan.'
'Marc will be acting as your captor-liaison contact point.'
The Doctor: 'I always have a finely detailed and well thought-out plan.'
Sarah: 'Okay, so what is it?'
The Doctor: 'Well, I really don't know. I'm sort of improvising as I go at the moment.'
Continuity: I2's logo is a cube with an inset eye, visible through the open facets. The name stands for Integrated Intelligence. They have been around, and becoming a major player, for the last five years - but to Vorell and the XNet family of products.
COBRA is the Commons Office Briefing Room something or other, who decide things such as raids on hostage situations. There's a ministry of Information Technology.
Economic growth is in single digits, according to a newspaper headline. Ninety-seven is a bad vintage of Ginger Beer.
The Little Brothers are a terrorist group opposed to government intervention or regulation.
Harry got posted onto some hush-hush stuff at Porton Down (see Harry Sullivan's War) after UNIT before becoming first an advisor, then a field officer, then an Assistant Chief of Staff for MI5 (one of dozens). He has a company BMW (with bullet-proof windows), but misses his old MG.
According to the Doctor, the TARDIS is too advanced to be able to read a CD ROM.
Sarah's editor on Metropolitan was Percy Wolnough. [The Ghost of N-Space says it was a woman called Clorinda. Obviously she moved on between then and The Seeds of Doom.] Percy now works for the Financial Times.
The Doctor can write decryption algorithms for computers, but has very little experience of toilets. He has an impossibly long metal pointer up his sleeve.
Vorella is a small planet in the Fratris System, whose dominant species (the Vorellans) was reptilian. A planetary computer network, Voracia, took over but was beaten by the organic natives. Voracia undertook a pilot study, that suggested organic components could improve efficiency. The results were the Voracians.
The SAS's Sea King helicopters use Stinger missiles.
MI5 had information about the Russian coup (presumably the fall of the Soviet Union) before the news agencies did, because they saw internet postings by students in Moscow.
Bambera is still the brigadier in charge of UNIT by 1998.
Links: The Doctor and Sarah have missed when they were aiming for, and the Doctor blames it on the Helmic regulators. Sarah last saw Harry only a month ago in her timestream. There's a mention of the TV show Nightshade from Nightshade, and a couple of references to Harry Sullivan's War. Sarah has written for "Metropolitan" on "the dangers of meditation" (Planet of the Spiders) and "the sudden evacuation of London all those years ago" (The Dinosaur Invasion). The Doctor's CV mentions degrees from the Prydonian Academy (The Hand of Fear, The Deadly Assassin) and "Lister, 1880" (The Moonbase).
Location: London and Hubway (in Wiltshire), 1998 'Not one of my favourites, but I'm sure it will do.' It's about 20 years after Sarah's time. Hubway officially goes on line on a Thursday (As it's 3 days early, it was originally meant to be a Sunday!)
Unrecorded Adventures: The Doctor had to come to the MI5 building with the Brigadier on several occasions to justify UNIT's existence and budget.
The Bottom Line: A well paced, well plotted story. The Doctor and Sarah are just right and Harry's return is well done.