Roots: Sherazade, Tom's Midnight Garden (the protagonist stays at a remote cottage kept by a reclusive landlady. When the resident clock strikes thirteen strange things become apparent), Walt Whitman's O Captain! My Captain!, Blake's The Tyger ("by whose hand - whose immortal eye?"). The Doctor quotes from Frankenstein and says of the Hornet-filled Noggins "he was Legion' (Luke 8:30) - he also likens him on their first meeting to the Norse god Odin. Later he suggests Noggins act as a Pied Piper. He compares his stuffed assailants to "a crazed cast of The Wind in the Willows). The scenario of narrated-tale-with-housekeeper recalls the Sherlock Holmes stories (with Holmes relating stories to Watson while his landlady is Mrs Hudson).
Dialogue Triumphs: "I don't do fear, really. I can never take it seriously."
Double Entendres: "What had I smoked from the badger's brain?" [that's a very good question, Mr Magrs]
Intertextuality: On reminiscing about insect races he has got along with, the Doctor mentions the Wrarth Warriors, galactic policemen who featured in the DWM comic strip The Star Beast. The Doctor's comment about making a few "short trips and sidesteps" may be a reference to the BBC Doctor Who short story anthology of the same name (Magrs supplied the Sherazade-esque First Doctor and Susan story The Longest Story in the World for the volume).
Continuity: The Hornets in this story are revealed to be an alien species, smaller and faster than 'land-dwelling' (i.e. terrestrial) species. While their stings singularly are probably ineffective in the main en masse they are quite deadly. They have a queen and can hear the thoughts of others, apparently. Recent deaths of high-ranking civil servants that the Doctor attributes to the Hornets' presence include a cabinet minister trampled in his own bed by an alpine ibex, a top-secret government think-tank cocktail party broken up (with key identities squashed) by a rampaging elephant, a nuclear arms expert crushed and devoured by a python in her bath, and the Minister for transport mauled by wild dogs in a corner shop.
The Nest is the Doctor's 'home away from home'; a rather run-down two-storey home in the Sussex countryside. It has a cellar (where among a lot of paraphernalia and rubbish the TARDIS' dimensional stabiliser lies), a study (containing a stuffed giant hare and snow leopard), a kitchen and a guest room (containing a stuffed owl). It is kept by the Doctor's recent housekeeper, Mrs Wibbsey. Among its 'extensive collection' of "rum" books (according to Mike) is an 'almanac of curious happenings'. The Nest also has a grandfather clock that strikes thirteen on the first appearance of the Doctor, and the Doctor keeps a full-grown wolf hound called Captain.
The TARDIS isn't present (presumably thereby hangs a tale), and the Doctor has cannibalised some of her dimensional stabiliser circuitry to erect a "semi-permeable" (otherwise the milkman would get suspicious) force shield around the Nest. The Doctor's sonic screwdriver proves useless against a rusted, poor-quality lock (although a paperclip does the job effectively).
Mike Yates has retired from military service 'quite some time ago' but still may have his service revolver. He and the Doctor met once since he left UNIT (see: Links), and he heard later that the Doctor had changed twice since. The job advertisement the Doctor places in the Country Times seems specifically aimed at him (see: Links)
During a series of 'short trips and side steps' the Doctor battles with the Hornets in many different times and places [these are, presumably, the latter stories of this series].
He still hasn't updated the photo on his UNIT pass since his last incarnation and complains that his joints are rather stiff. The anecdotes he tells Mike suggest that this story takes place after Leela has left him (The Invasion of Time) and before he is summoned by the White Guardian (The Ribos Operation)
Untelevised Adventures: In the Doctor's lounge room Mike discovers a Polaroid of what appears to be the Doctor at Nelson's funeral.
The Fourth Doctor and Mike met once before, as a Christmas party hosted by the Brigadier.
The Doctor claims he once travelled with a rather 'argumentative' female dodo [although he may have been referring to Dodo Chaplet]
Mike asks the Doctor (obliquely) if he counts William Blake as a personal friend - the Doctor doesn't refute this.
Links: Mike mentions "Miss Grant" and "Miss Smith", Metebelis Three (Planet of the Spiders) and 'the anti-matter universe' (The Three Doctors). During their first evening of reminiscences the Doctor tells Mike of his recent adventures, including encounters with 'giant rats (The Talons of Weng-Chiang), 'killer robots' (The Robots of Death) and 'skulls from the dawn of time' (Image of the Fendahl) and later mentions UNIT and the Brigadier. Mike recalls the Master and the Axons (The Claws of Axos). Among a short list of insect races he doesn't get along with the Doctor mentions Wirrn (The Ark in Space) and Zarbi (The Web Planet). Among the job experiences the Doctor requests in his advertisement are 'giant maggots' (The Green Death), 'super-intelligent spiders' (Planet of the Spiders again) and 'prehistoric monsters' (Invasion of the Dinosaurs).
Location: 22nd of December (just after the Winter Solstice) 2009, 'Deepest' Sussex.
The Bottom Line: "Aaah... marmalade and bacon, squashed together in a sandwich just so!!"