Cat's Cradle: Witch Mark
Roots: Celtic (particularly Irish) Mythology, The Lord of the Rings and the Hobbit.
Goofs: Many of the references to Celtic mythology are inaccurate, but this is partly intentional.
On page 39, there's a sticker claiming that it's against the law to sell cigarettes to under-18s, when it should be under-16s.
Ace is disturbed at the taste of the Dinorben food, but surely she would be comparing it to the probably not dissimilar fare she had without complaint in Mesopotamia (Timewyrm: Genesys) rather than modern foodstuffs.
It's never explained how David is a witch. [We can guess that he got swapped on his holiday in Wales aged 5].
The fake Doctor and Ace appear out of nowhere and then just disappear from the plot.
Technobabble: Semiorganic silicate computer transfer device.
Dialogue Disasters: The Doctor: 'Well, well, well.'
Ace: 'Three holes in the ground.'
All the puns on Caeryon's name.
The Doctor: 'Nothing would give us greater pleasure, but as you're offering, I'll have to put off nothing.'
The Doctor on megalomaniacs: 'Always follow the same pattern. Genius with a deviant childhood, forced to eat liver, too much vitamin A, becomes ambitious, develops a taste for power. Before you know it they're trying to take over the universe and looking for someone to gloat at. Of course, sometimes they just become traffic wardens.'
Dialogue Triumphs: The Doctor: 'Ace, you shouldn't play records in other people's houses when they're trying to sleep.
Ace: 'Right-o, Professor. I'll bear that in mind.'
The Doctor: 'There are some ways of descending hills that are more decorus for a young lady than others, my dear Ace.'
Ace: 'I bet they're all boring though, aren't they?'
Bathsheba: 'How does it work?'
The Doctor: 'Well, have you got a few days for me to explain some fundamental physical principles to you?'
Bats: 'You intend to breach the wall?'
Ace: 'I'm going to blow it to bits.'
Continuity: There are a range of peoples in Tir Na N-Óg. They include the Ceffyl (time-sensitive Unicorns), Sidhe (humanoid foxes), Firbolg (Centaurs), Fomoir (trolls) and humans. They measure distance in Ells. It is located on the edge of the galaxy. The humans are ruled by a high council - the Tuatha de Danaan. The other species, and some of the humans, have a Troifan numeral on their bodies. It is called the Witch Mark, and humans with it are often burnt. There are dragons, which are bio-mechanoids.
The TARDIS uses morphologically unstable living organic matter to handle its block transfer computations (Logopolis, Castrovalva). There are very few places to get this kind of matter. They include Gallifrey, perhaps Axos (The Claws of Axos), and maybe Nestene matter (Spearhead from Space, Terror of the Autons). [A Rutan might work as well]. We see a cupboard built into the roundelled walls.
New Scotland Yard has a one-man Paranormal Investigations Team.
The Doctor's Respiratory Bypass (Pyramids of Mars) misses out the olfactory organs (nose). The Doctor appears to not be a vegetarian. [He is, but is just cooking bacon for everyone else].
The Book of Rassilon starts with 'In the beginning'
Ace is still biologically affected by her experiences on the Cheetah planet in Survival. She's still using plain old nitro-nine. [What did happen to nine-a from Timewyrm: Exodus?]
The Doctor has told Ace that examples of actual evolution are quite rare in Earth science, and that in the Universe all the theories of species development have some validity. [I think that might make him a creationist.]
Troifans are fanatical about research - half their planet is a university. They try to do things bigger and better than the next race. They mark their experiments with a numeral to show which experiment they are from. They have ratified the Galactic Constitutional Regulations regarding interference with species.
Earth is widely recognised as one of the causal nexus points of the galaxy.
The Brigadier is, apparently, very fond of horses.
Links: This story is the final book in theCat's Cradle series, and follows on from the other two books - Time's Crucible and Warhead. We see TARDIS features first seen in Logopolis and The Daleks. Ace comes across a TARDIS workshop that has been occupied 'quite recently'. This was intended to be a reference to The Invasion of Time, saying that time in the TARDIS flows differently. It is as likely to have been used in an unrecorded adventure. The Doctor mentions almost being killed by a spider (Planet of the Spiders). Ace mentions her time as a waitress (Dragonfire, also mentioned in The Crystal Bucephalus)
There are minor references to An Unearthly Child, Inferno, Delta and the Bannermen, Remembrance of the Daleks, Battlefield, The Curse of Fenric, and Survival.
Location: Tír Na n-Óg and Wales. The setting is contemporary. It's early summer, before London phone codes changed to 071/081 - so the early 90s.
Unrecorded Adventures: The seventh Doctor and Mel ('the squeaky one') visited Llanfer Ceriog and met Old Davy. This was 7 years before this story. The Doctor mentions previous excellent meals - "Lucretia, Stephen, Elizabeth" -whose coronation Essex spoiled by throwing drumsticks around. The Doctor claims to have written some of Greek Literature (and read all of the rest). He thinks he might have helped write one of the lines of the Bible (Byzantium! and The Plotters)
The Bottom Line: Quite a successful jaunt into fantasy territory. Everyone's well-written, and Tír Na n-Óg is a fairly well-thought out world. Early on, the book successfully builds up the mystery of what's going on and the revelations are well-paced. The journey through Tír Na n-Óg to meet Goibhnie isn't particularly inspired, but the rest of the book more than makes up for it.