Roots: Rookwood, the true (and fictitious) story of Dick Turpin. Moll Flanders, Robinson Crusoe, and Gulliver's Travels (the Dr is referred to as a 'Yahoo' and Eleanor a 'Hounhim'). His Girl Friday. Dick refers to (a fictional-become-real?) Robin Hood, and he and 'Gypsy Charlotte' quote Adam Ant's Stand and Deliver. The Grel read from A Tale of Two Cities ("It was the best of times, it was the worst of times") and The House That Jack Built. Dickens is name checked, as is Thackeray. while Charley quotes Edward Bulyer-Lytton's Richelieu; Or the Conspiracy ("the pen is mightier than the sword") and likens herself to 'the Boy Who Cried Wolf.' Rosemary as an aid for remembrance is a traditional belief, popularised in Hamlet IV(v) Sherlock Holmes ("If you eliminate...") and Shakespeare's Falstaff.
Intertextuality: The Grel first appeared in Paul Cornell's Virgin Books Bernice Summerfield New Adventure Oh No, It Isn't! and following its audio adaptation by Big Finish continued to reappear intermittently in the Bernice Summerfield audios.
Dialogue Triumphs: "It might be a blessing in disguise" "-It's a very good disguise!"
"It must be much easier to be fictional; you never have to visit the lavatory for a start."
"Words on a page, however skilfully written, can never convey the realities of losing a loved one; neither can mere words fully convey joy or love or hope. If you choose to live in a world where your grief is unreal, then you can never again experience true happiness."
"'Everything' is rather a tall order, even for me"
Double Entendres: "Damn it, Dick - fire!"
"You are only inches from my face, yet I can scarce see you, Dick"
"I'm not taking it slowly so you can ride daintily side-saddle."
"Look what you've done to Rookwood!"
Continuity: The motto of the libraries on Alexandria IV is "Let the punishment suit the crime", and the Doctor suggests that the penalties for overdue books can be strict and painful.
The Grel are cephalopods - they breathe through gills, filtering the air and as they have no noses, lack a sense of smell. They have a near pathological obsession with separating fact from fiction.
The TARDIS' storage area appears to be able to mask any signals pertaining to items held there from outside parties - in this story it is only when Rookwood is removed from storage that the book's overdue status triggers the Alexandrian Reminder Bot.
The Doctor claims his doctorate isn't in medicine. He says his Time Lord "phagocytes" render him immune to the Grel particles (though the bouquet of rosemary does its work as well.) The copy of Rookwood he has borrowed from Alexandrios IV is over three hundred years overdue.
Links: The Doctor reuses the 'liar's paradox' - the logic puzzle with which he successfully confounded BOSS, on the Grel (The Green Death) The Doctor's suggestion of the Grel particles being due to nanoparticles, or may be viral in origin may be a hint towards the wider Viyran Strand
Q.v: 'The Viyran Strand', 'The Doctor's Doctorate'
Untelevised Adventures: The Doctor says he met Capability Brown and once witnessed him move an entire lake six feet to the left. The Doctor borrowed Rookwood from the library of Alexandria IV at a time when the story's Gothic themes were of interest to him [his early Fourth incarnation, perhaps?] but lost interest before he even began to read it.
The Bottom Line: "Sounds a most edifying tome..."
Another romp through the English canon, made clever this time by having Charley more knowledgeable of a book's contents than the Doctor. Silly in places, and ridiculous in others (giant Turpin), it's quite harmless and as good a 'straight' adventure for the Sixth Doctor and Charley as you're likely to find.