[[caption-width-right:350:Romana in the version filmed for TV broadcast.]]

->'''The Doctor:''' When I was on the river, I heard a strange babble of inhuman voices. Didn't you, Romana?\\
'''Romana:''' Yes.\\
'''Professor Chronotis:''' Oh, undergraduates talking to each other, I expect. I've tried to have it banned.

The one screwed over by a WritersStrike.

Filming on "Shada" ("SHAH-duh"), which was interrupted by the 1979 BBC strike, was never completed. It remains the only story of Classic Who that got to the filming stage of production without having been aired on television. But Creator/DouglasAdams scripts aren't so common that they can be discarded so easily, and eventually ''three'' official versions saw the light of day.

The first was the incomplete filmed version. Clips from this episode were initially re-used in "[[Recap/DoctorWho20thASTheFiveDoctors The Five Doctors]]", which saw the Doctor and Romana time-scooped out of the "Shada" plot altogether. In 1992, a full episode was finally cobbled together out of the existing bits, with linking narration provided by Creator/TomBaker -- appearing as a curator ([[{{Recap/DoctorWho50thASTheDayOfTheDoctor}} ho ho]]) in a museum full of old ''Series/DoctorWho'' things, and telling the story in first person.

A Creator/BigFinish-produced audio (also available for free with some [[http://www.bbc.co.uk/doctorwho/classic/webcasts/shada web-animation]]) was recorded from the full script in 2003. It stars the Eighth Doctor Creator/{{Paul McGann}} as the story's Doctor, and Romana during her time as President of Gallifrey, as per AudioPlay/BigFinishDoctorWho canon. In this version of events, the two decide to investigate what should have happened when they were [[Recap/DoctorWho20thASTheFiveDoctors time-scooped]] out of their previous attempt to have this adventure.

Finally, a 2012 [[Literature/DoctorWhoNovelisations novelisation]] was written by Gareth Roberts, based on the final versions of the scripts.

Dougles Adams ended up recycling entire chunks of the plot, as well as the character of Professor Chronotis, into ''Literature/DirkGentlysHolisticDetectiveAgency''.

[[caption-width-right:164:Romana in the webcast version.]]

One day, the Doctor gets an invitation from Professor Chronotis, a retired Time Lord posing as an eccentric old Cambridge don. He and Romana drop by St. Cedd's College, Cambridge, in 1979.

Chronotis is extremely old, even for a Time Lord, which makes his memory spotty and unreliable... but after some gentle prompting, he eventually remembers that he'd wanted the Doctor to take a certain book back to Gallifrey. No ''ordinary'' book, this, but an ancient relic from the days of Rassilon, the founder of Time Lord society, and possibly (read: almost certainly) full of uncertain and dangerous powers. The three Time Lords begin to search Chronotis' flat for it.

Unfortunately, Chronotis has already forgotten that he'd just that morning lent it out to physics student Chris Parsons -- who's taken his new toy over to the lab to examine it, with baffled fascination, and even asked his girlfriend Clare to come have a look.

Even ''more'' unfortunately, someone else is after the book, too: a guy named Skagra, and with a name like that he's ''got'' to be evil. Skagra's putting the finishing touches on a brain-in-a-jar -- actually, a collection of great minds, whom he'd lured into working with him under false pretenses and then mind-napped -- and just needs one more mind. Specifically, he wants the mind of legendary Time Lord criminal Salyavin, who was said to have the power to project his own mind into other minds; with this power in Skagra's brain jar, he'd be able to control the rest of the universe. Salyavin is imprisoned on the prison planet of Shada, whose location has been lost for centuries, but Skagra is convinced that the directions are in Chronotis' book.

By the time Chronotis remembers Chris Parsons' name (going through the alphabet until he reaches "Y"... "Young Parsons!"), Skagra has parked his spaceship outside town and gotten a lift to St Cedd's. The Doctor's just left, though -- he's borrowed a bike and gone off to fetch Chris from the physics lab, little realizing that the guy he nearly crashed into on the way was Chris himself, on ''his'' way to see Chronotis to ask about the book.

The Doctor does meet Clare at the lab; with her in tow, and in possession of the book, they return to Chronotis' flat -- to find the old professor dead, killed by Skagra while Romana was in the TARDIS looking for milk for the tea. With the help of some Time Lord technology, Chronotis manages to convey a final message: watch out for Shada.

Shada turns out to be a prison planet, and the gang soon all find themselves there. The Doctor is (of course) captured by Skagra, fibs his way through an interrogation by pretending to be ''really'' dumb, and is promptly killed by a very annoyed Skagra. However, the Doctor knows enough about this sort of thing to relax his mind at the last moment, meaning Skagra only gets a ''copy'' of his memories and the Doctor continues to live. He convinces Skagra's ship that, since he's now dead, he's not a threat anymore and the ship can freely listen to him. The ship is a bit confused, but rolls with it.

Professor Chronotis, meanwhile, is OnlyMostlyDead and uses Clare to track down the others (using his TARDIS, which turns out to be have been ''his living room'' all along). He also turns out to be Salyavin. Once the Doctor rejoins the plot (after taking a short unprotected trip directly through the vortex and MacGyvering one very silly mind-shielding helmet), he's able to mind-control Skagra's golems and prevent the AssimilationPlot. He and Romana decide to simply drop Chronotis/Salyavin off back home, since rumours of his great evil were probably for the most part just exaggerated nonsense. The Doctor wonders if people will say the same about him someday.


* ActuallyIAmHim
* AccidentalMisnaming: Chris introduces himself as "Chris Parsons, Bristol Grammar School". The Doctor appears to misparse this phrase, and refers to Chris as "Bristol" thereafter.
* AdaptationExpansion: The novelisation adds an opening chapter focusing on Skagra.
** There are added scenes featuring Chris walking around the TARDIS and finding his bedroom.
** The closing of the novel adds a scene of Chris, Clare and Chronotis being escorted to the police station, and a scene of the Doctor and Romana using the Randomiser in the TARDIS.
* AdaptationalAttractiveness: The animated version sexes up Claire from a woman dressed in mainstream (and nowadays slightly silly) late-70s fashion into a late-70s British [[PunkRock Punk]], bondage gear and all. Chronotis is also much more handsome.
** The book version turns Clare back into a mainstream 70s chick (even mentioning a complaint from her about a poodle perm she washed out) and Chronotis into an extremely old and silly man, but Skagra is described as extremely, androgynously beautiful, especially his 'full, sensual lips'. A side character expresses amazement that even though Skagra has a facial scar, it's a [[GoodScarsEvilScars sexy one instead of a disfiguring one]].
*** Well, he was played by Christopher Neame in the TV version, and Neame was [[PrettyBoy very pretty]] back in the 1970s. Seriously, go and Google him if you don't believe me.
** DiscussedTrope InUniverse in the book, when Romana sees the Outlaws, ancient murderers, tyrants and terrorists of Gallifreyan history she used to have nightmares about as a child, based on a children's picture book she used to have called "Our Planet Story". She sees that the real Lady Scintilla is very different to the drawing of her in the book, which portrayed her as a tall, imperious IceQueen, remarking that she's actually short and 'dumpy' - but she still possesses razor-sharp, blood red FemmeFatalons.
* AdaptationalHeroism: From the TV version to the webcast to the novelisation, Salyavin moves from a reformed villain to someone who was never actually a villain at all, but just misunderstood.
* AdaptationalSexuality: In the book, David (a VictimOfTheWeek character murdered by Skagra) is shown in his internal monologue to be gay, talking about gay clubs and worrying that his taste for Cilla Black is a bit too stereotypical. This is also used to explain his relative generosity towards Skagra, being that he fancies him and has mistaken Skagra's demands as a come-on. BuryYourGays UnfortunateImplications are somewhat averted, since the Doctor eventually implants David's consciousness into an extremely handsome artificial body as well as reuniting him with his mother.
* AlphabeticalThemeNaming: Names of major heroic characters and places introduced in the story begin with the letter "C" - Chris, Claire/Clare, Chronotis, Cedd's College. Names of major villanous characters and places begin with the letter "S" - Skagra, Shada, Salvayin, Sujatric and Rundgar, Scintilla, the Ship. Lampshaded in the book by Chris who complains that he can't remember any more stupid names that begin with "S".
* AssimilationPlot: "The Universe, Doctor, as you so crudely put it, will not be ''mine'', the Universe will be ''me!''"
* AuthorAppeal: Creator/DouglasAdams set the story in his own Cambridge University.
* BrainInAJar
* BreakTheHaughty: Skagra. We first assume he is an EvilGenius and a totally logical, emotionless overlord, but we begin to realise he's actually an awkward nerd, alienated by his incredible intelligence and socially tone-deaf as a result, who is [[IJustWantToBeSpecial in love with an image of himself as a logical, emotionless overlord]]. His breakdown is caused by the Doctor, who [[TricksterArchetype enjoys being intentionally annoying]], managing finally to get under his skin enough that he begins to act like the tantruming ManChild that he is.
* CallForward: The novelization casually references concepts and characters introduced after Creator/TomBaker left the show, up to and including [[Recap/DoctorWhoS32E4TheDoctorsWife the Corsair]].
* CaptainObvious:
-->'''Romana:''' (To the unconscious Professor Chronotis) Professor!\\
'''K9:''' No response, Mistress.
* ContinuitySnarl: So... which version of "Shada" ''really'' happened? Did Romana and the Fourth Doctor meet Chronotis, or did the events of "[[Recap/DoctorWho20thASTheFiveDoctors The Five Doctors]]" distract them and it wasn't until four lives later the Doctor remembered to go back? And of course the script and the novelisation don't ''entirely'' match. We'll probably just have to blame the Time War..
* DiscoDan: In the novel, Chris is a mild example. His [[SeventiesHair long hair]] and flared trousers are just starting to be very out of fashion in 1978, and he feels alienated by how all the young undergrads are dressed in tight jeans and short hair. He also gives preferential treatment to a student wearing a Music/JethroTull t-shirt because he feels like he looks more normal.
** Skagra unintentionally comes off as this because his ceremonial alien overlord gear looks to humans like a ridiculous disco costume, leading to passers-by to mock him in the street. He considers this to be awe.
* EndOfAnEra: Though never broadcast, this story marked the end of the following features of the show from a production standpoint:
** The 1967 arrangement of the theme by Delia Derbyshire.
** The tunnel opening sequence by Bernard Lodge and the diamond series logo introduced in "[[Recap/DoctorWhoS11E1TheTimeWarrior The Time Warrior]]".
** Graham Williams's tenure as producer; the rest of the show's original run would be produced by Creator/JohnNathanTurner.
** Creator/DouglasAdams's tenure as script editor.
** Dudley Simpson's tenure as incidental music composer.
** David Brierley as the voice of K9; John Leeson would reprise the role the following season onwards.
** The Fourth Doctor's multicolour scarf and brown frock coat; the following season would feature the Doctor (in Tom Baker's final season on the show) in a burgundy & purple scarf and a larger burgundy frock coat.
** The TARDIS prop designed by Barry Newberry; the next nine years of the show's original run would utilize a new, fibreglass prop designed by Tom Yardley-Jones.
** The use of six-part stories; all future serials would span four parts at most.
* EveryoneKnowsMorse: Although in this case it's Gallifreyan Morse.
* {{Expy}}: Professor Chronotis is something of an Expy of the retired Fourth Doctor Creator/DouglasAdams originally wanted to write this serial about. Later, another expy of the Fourth Doctor (Dirk Gently) and an expy of Chris (Richard) showed up in ''Literature/DirkGentlysHolisticDetectiveAgency'', starring alongside a {{Transplant}}ed Professor Chronotis. The character of the Curator in "Day of the Doctor" owes rather a lot to Chronotis as well.
* FanGirl: The book version of the Ship is fascinated by the Doctor and starts seeking out and watching old holographic video footage of his adventures, which are strongly implied to just be ''Doctor Who'' episodes. She becomes a serious fan, and eventually forces Skagra to watch them all with her in the hope that he'll learn some good moral lessons from the stories. (The script has elements of this, but the novel really plays them up.)
* FreudianExcuse: Spoofed in the book. Skagra talks about his planet to Romana, explaining how a rogue Time Lord conquered his planet, brainwashed the populace and, when he eventually left for Gallifrey again, the people were unable to handle their own emotions after centuries of repression and tore each other apart in an unspeakable war that almost destroyed the entire planet. Romana is horrified and expresses pity for his people, until Skagra informs her that it happened thousands of years before he was born and that they were not his people. He then shows her the planet from ''his'' point in history, a rich, laid-back, beachy PleasurePlanet with a primary import of ice cream. Romana is slightly less able to sympathise with this, no matter how much he insists that his people's shallowness and consumerism was unbearable to someone as brilliant and clever as him.
* FunctionalGenreSavvy: In the book, the Doctor appears to project this into people around him, as a kind of force-of-personality-transmitted TheoryOfNarrativeCausality, railroading his accomplices into the role of TheWatson regardless of how they might feel about it.
** Clare gets a [[MetaGuy whole scene where she realises that she is like this]] and, as a result, is incapable of reacting sensibly towards the huge RummageSaleReject eccentric who claims to be an alien looking through her stuff - instead describing that she feels an inexplicable love and generosity towards him as if he was a [[FandomNod nostalgic fixture of her childhood]], and a strong desire for him to ''take her with him''. She knows she should be intimidated and trying to get rid of him, but instead feels that she has no choice but to find him charming, [[TheWatson ask helpful questions and do whatever he asks her to]].
** The book's version of Chris is somewhat less like this, as he's mainly concerned with the long-term scientific implications of everything that happens to him, but he also has his moments - as he hangs around the Doctor, despite becoming braver and more curious, he also sinks further into being a NonActionGuy, commenting in his internal monologue that helping out the Doctor just makes you feel all "girly", sweetly curious and dependent on him for protection.
* GoneHorriblyRight: The Doctor convinces the computer that he's dead and [[Literature/{{Redwall}} a dead enemy ain't an enemy no more]]. However, "dead men do not require oxygen."
* GrandTheftMe
* HateDumb: Skagra's hatred for the Doctor is played like this in the novelisation, as a form of FandomNod. He spends a good deal of time watching archive footage of the Fourth Doctor's adventures, and criticises them in the same manner of a fan criticising the writing and acting of ''Doctor Who'' serials. His hatred for the Doctor builds, to the point where he eventually has a vision of his future and is horrified and confused to discover that it is apparently "the Doctor, forever". We find out why this is when his eventual CoolAndUnusualPunishment is to be imprisoned inside a room with an in-universe ''Doctor Who'' fangirl who wants him to watch every single record of his adventures, with her {{Squee}}ing about it the whole time, in order (starting with a description of the first shot of the first episode of the ''Doctor Who'' TV show, just so we get the message). This reduces him to howls of {{Angrish}}.
* HamToHamCombat: Paul [=McGann=] vs Andrew Sachs, in the Creator/BigFinish audio version. It's [[CrowningMomentOfFunny rather magnificent]].
* HeelFaceTurn: In some versions, Salyavin, aka Professor Chronotis. In the novelization, this does not apply as Salyavin was never actually evil to begin with.
* HotterAndSexier: For some reason, the animated version's Claire is a lot less conservatively and more punkishly costumed than the live-action version, with a pink fluffy [[SweaterGirl sweater]] showing quite a bit of cleavage, a goth-influenced make-up job, and a ''studded leather dog collar''. The animated Chronotis is also [[GrandpaWhatMassiveHotnessYouHave rather more well-preserved]] than the live-action one.
** The book plays the Doctor's [[CargoShip relationship with Skagra's Ship]] with copious DoesThisRemindYouOfAnything, making it resemble an affair between an open-minded stranger and a sexually-repressed housewife sneaking around behind the back of her JerkAss husband. For instance, when he teaches her how to open a time Vortex, this is played as if he's giving her her first orgasm. Seduction of [[LoveRedeems eventually helpful female characters]] is much more of an Eleventh Doctor move than a Fourth and wouldn't happen in the show of that era. Of course, the book's writer wrote most of his episodes for Matt Smith's run.
** The book's version of Clare's first visit to Professor Chronitis's study. In the filmed version she's neatly buttoned up with her hair in a prim bun, in the book she's dishevelled in a way that automatically makes Willkins assume she's sneaking out of a male student's digs, or possibly a male don's study (but not Chronitis's. He's such a nice old man.)
* InkSuitActor: In the animated version. Obviously this is required for the Eighth Doctor and Romana since they appeared in live-action TV, but it extends to the human and humanoid guest characters, who look much more like their voice actors than the actors in the live-action version.
* InsaneTrollLogic: The Doctor convincing the ship's computer that he is dead "in a fabulous display of illogic logic" in order to get it to release Chris and K-9.
* IWasQuiteALooker: Chronotis. Justified in that between his handsome young appearance, seen briefly by the Doctor in a psychic vision, and the way he looks now, he not only aged about 900 years but regenerated.
* LargeHam: The audio version features an incredibly Hammy turn from Andrew Sachs of ''Series/FawltyTowers'' fame as the [[SissyVillain hysterically camp]] BigBad Skagra.
-->"''REMOVE'' all the contents of his ''MIND?'' Why not? [[EvilLaugh Muah-ha-ha!]] ''[[EvilLaugh Muah-HA-HA!]]'' '''[[UpToEleven AH-HAH-HA-HA-HAAAA!]]'''"
* LeaningOnTheFourthWall: The book makes multiple references to how 1970s ''Doctor Who'' was originally broadcast in serial format on Saturday evenings, to the point that it's a RunningGag:
--> For goodness' sakes, thought the Doctor, why weren't all these tourists, roadies and nuns at home watching television on a Saturday evening like normal people.
--> He... permitted himself just a tinge of inward pleasure at the thought of scrambled eggs on toast and the BBC's Saturday serial in a few hours...
--> The Doctor's shoulders slumped. 'And I usually like Saturdays,' he said.
* LettingHerHairDown: Clare in the live-action TV version, after she accidentally takes Chronotis's TARDIS off.
* LiteralMinded: Neither rhetorical questions nor expletives are a particularly good idea around K-9.
* LogicBomb: The Doctor gets attacked by Skagra while snooping around his ship. After the villain attacks the Doctor, the Doctor puts himself into a state of FauxDeath thanks to his BizarreAlienBiology so he can escape. During this, The Ship, who is extremely obsequious towards the villain, scans the Doctor and confirms him dead. When the Doctor gets up and starts walking around and talking to it, the Ship is extremely confused, since it can't understand why he is talking if he is dead, and suggests rescanning him. At this point, the Doctor takes advantage of the situation by convincing it that the Ship does not need to rescan him, as her master is infallible, and she is therefore infallible. Therefore, her reading was right, the Doctor is dead, and as he is dead he cannot order her to do anything that would cause any harm to her or to her master, [[InsaneTrollLogic so she should start obeying his commands]]. The Ship starts listening to him, but [[GoneHorriblyRight also turns off the oxygen as there are no live people on board, and finds the Doctor's request to turn it back on illogical]]. In the book adaptation, the increasing demands the Doctor's logic puts on her causes her to reassess much of her basic programming, realise that her master is not infallible, that he tried to kill her, and that the Doctor is a much better person than him.
* {{MacGuffin}}: The book.
* MagneticHero: Lampshaded in the novelisation, where Clare, who is [[MetaGuy unusually clever]], notices the magnetic effect that the Doctor has on her mind (depicted as being borderline EmotionControl) and finds it a bit creepy, not to mention a bit sexist as she finds herself acting like a NeutralFemale as a result. Her attempts to ''defy'' her desire to love and trust the Doctor and do everything he says drive her to start solving the mystery herself, leading to her accidentally launching the TARDIS of a retired Time Lord.
* MindRape: The first victims of Skagra's device. Most victims are simply killed, but the first six people were left alive and so nonfunctional by the experience that they are unable to talk or care for themselves. The Doctor is eventually able to communicate with Akrotiri, one of the victims, by connecting Chris's brain to his - and Akrotiri's brain is so wrecked that the experience is excruciatingly painful for Chris (defying this trope, the Doctor tells Chris that this might happen and gets his consent first).
* MyNaymeIs: For some reason, Clare is spelt without an "i" in the script book and credits of the video version. The webcast goes for the standard spelling, and the novel turns this oddity into a CallForward.
* MythologyGag:
** Throughout the story, ''The Worshipful and Ancient Law of Gallifrey'' is described as "a small red book, about five inches by seven". The paperback edition of Gareth Roberts' 2012 novelisation is a red book. It's five inches wide and seven (and a half, admittedly) inches tall. (This is also an allusion to a basically identical cover art/book MacGuffin gag being used in ''Literature/TheHitchhikersGuideToTheGalaxy''.)
** In the closing scene of all versions, the Doctor ponders a future in which he retires and everyone assumes he's just a "[[RunningGag nice old man]]". This is a reference to the original Douglas Adams story written for this serial slot - a story about the Doctor retiring from his travels, an idea that excited him but was killed by ExecutiveMeddling.
* NamedByTheAdaptation: David Taylor.
* NiceHat: Romana again. Just check out the page image.
* NotSoStoic: Skagra. In the book, we are repeatedly reminded that he allows himself only two smiles a day and lives only on logic. The Doctor teases him about this, joking that he'll end up getting a 'mad gleam in the eye' and start saying things like "[[IncomingHam The universe belongs to me!]]", since [[WorldOfHam that's what everyone else he deals with does]], but Skagra remains impenetrable, if a little bit more attracted to Romana than he'll even admit to himself. Until his plan suddenly implodes in a way none of them saw coming, after which Chris observes Skagra crying uncontrollably in the arms of his sworn enemy the Doctor, who has bundled him up in his coat [[AllLovingHero like he's trying to console a small child]]. Even though he gets his plan back on the rails after this, the mask has well and truly slipped, and he goes straight into the 'mad gleam' mode that the Doctor told him would happen.
* {{Oxbridge}}: Fictional Cedd's College in actual Cambridge.
* PardonMyKlingon: In the book, the Doctor at one point uses an Old High Gallifreyan swear word which is left in the text as symbol form. It is described in the footnote as untranslatable and descriptive of something far more obscene than any of the readers can apparently imagine, although [[PrecisionFStrike it's first used in the form "___ you" and the first of the symbols looks quite a lot like a linked male-and-female symbol]].
** Parodied when Romana is shocked to discover a note from a criminal depicting the rudest Gallifreyan symbol, "the V of Rassilon". We do eventually get to see the note, and it's just a passable illustration of a hand doing the VSign (set in some interlocking shapes that imitate post-ReTool depictions of Gallifreyan writing).
* {{Pastiche}}: Gareth Roberts' novelisation is written as a pastiche of ''Literature/TheHitchhikersGuideToTheGalaxy'' as a MythologyGag.
* PenalColony: Shada itself.
* PragmaticAdaptation: The novelisation is something of an extreme example, incorporating information from what footage was completed, the known script, some WordOfGod, Creator/TomBaker's copy of the script into which he had [[LargeHam handwritten a bunch of extra jokes and stage directions for himself]], two pages of notepaper with an entirely unknown scene handwritten by Creator/DouglasAdams, the Big Finish audio adaptation (which starred the Eighth Doctor) and even some borrowings from ''Literature/DirkGentlysHolisticDetectiveAgency'', in which a lot of ideas for "Shada" were reused - and that's before the [[HotterAndSexier copious]] [[DenserAndWackier changes]] Gareth Roberts made to update the story to feel more like a modern ''Doctor Who'' story, expand on the characters, add {{Call Forward}}s and fanservice, and fix plotholes. Gareth Roberts wrote in the afterword about how he thought the weaknesses of "Shada" were not down to any weakness of Douglas Adams himself, but a result of the tight deadline the story was written in originally, evidenced by how well-done the groundwork was even where he had to fix things. For instance, the original has a part where Chris figures out TheReveal that Professor Chronotis is secretly the dangerous Time Lord criminal Salvayin, placed just as the Doctor has worked out that the villain needs Salvayin's unique ExpositionBeam {{Psychic Power}} for the plot to work, ''and'' just as the villain thinks Salvayin is lost forever. It seems obvious that Chris is going to announce this to the Doctor and the villain, with the best intentions, at the worst possible time - but Chronotis instead just [[IdiotBall announces his secret identity to everyone for no reason]]. Roberts changes this so that Chris blows it (bursting in on an added funny scene where the villain is in the throes of a VillainousBreakdown over his plan's failure and the Doctor is [[AllLovingHero giving his enemy a cuddle and reassurance]]), saying that this is certainly what Adams wanted to happen anyway, but probably was forced to keep an earlier draft of the scene due to time pressures. Roberts also gives Skagra a proper backstory, which was omitted from the show for time reasons, and deals more with the fallout of EccentricMentor Chronotis actually being a legendary {{Outlaw}} in disguise.
* PromotedToLoveInterest: In the novelization, the Doctor gets some fun sexual tension with a sentient spaceship. In the original her role is simply to be confused by him with a LogicBomb, but in the book the experience (along with him also teaching her how to time travel in a way suggestively related to him teaching her how to [[TheImmodestOrgasm orgasm]]) makes her curious about the world and eventually fall for the Doctor, who for his part is respectful but not very reciprocal of her feelings - though it's worth pointing out that when he attempts to guilt Skagra about trying to destroy the Ship, his retort (that 'a machine consciousness is worthless') is the ThisMeansWar moment.
* PunnyName: The men in the Think-Tank have weirdly jokey names, e.g. RAF Akrotiri (the name of an airforce base in Cyprus), GV Centauri (a star), AST Thira (Ast-Thira refers to a flight route within Greece.)
* PutOffTheirFood: Early in the episode, Chronotis offers to make tea for Chris. Chris changes his mind upon learning he apparently uses ''lumps'' of milk.
* SapientShip: Skagra's Ship, which he has programmed to have a matronly voice and to view Skagra with awe and worship. The Doctor inadvertently uses a small LogicBomb on it to get out of a scrape, and its attempts to reconcile the faulty logic with its observations lead to it questioning its entire worldview.
* ShaggySearchTechnique: Clare is searching Prof. Chronotis' study and discovers the controls to his TARDIS by leaning on a bookshelf.
* ShoutOut:
** In the animated version, the Doctor's brain-amplifying headgear is built around [[CallBack the Second Doctor's "witch's hat"]] and a [[Series/StarTrekTheNextGeneration spacesuit helmet labelled "NC-1701D"]].
** The VictimOfTheWeek in the webcast (David Taylor in the novel) is made into a vintage car enthusiast. He's particularly fond of the [[Franchise/TheHitchhikersGuideToTheGalaxy Ford Prefect]].
** In the novelization, Chronotis states that he replaced ''The Worshipful and Ancient Law of Gallifrey'' with "an Earth classic... [[Literature/TheHitchhikersGuideToTheGalaxy something about thumbing a lift,]] [[FandomNod and there were towels in it]]..."
** Multiple further MythologyGags about ''Hitchhiker's'' are made in the novelisation, such as Skagra's observation that the human economy seems to be based on moving small pieces of green paper around and that everyone is very excited about digital watches (a shoutout to the opening of ''Literature/TheRestaurantAtTheEdgeOfTheUniverse''), and Chronotis saying "Time! Don't talk to me about time!", a paraphrase of Marvin's famous line. Additionally, the whole book is written in a pretty obvious {{pastiche}} of Adams' writing style, which also counts as this.
** Creator/DouglasAdams named the characters of Chris Parsons and Clare Keightley after his friend Chris Keightley, president of the Cambridge Footlights.
** The Thinktank scientists all bore names associated with Greek islands: Caldera, Akrotiri, Ia, Santori and Thira.
* SiliconBasedLife: The Kraags, probably.
** In the BBC Video version, Creator/TomBaker states that they're made of "crystallized coal."
* SissyVillain: One of the flaws Creator/DouglasAdams noted about his script was that he'd written Skagra in this way, which he admitted was lazy on his part and neither funny nor frightening, especially in comparison to the dynamic and interesting villains in his much preferred script "[[Recap/DoctorWhoS17E2CityOfDeath City of Death]]". He is RescuedFromTheScrappyHeap in both the Creator/BigFinish adaptation (in which he gets a ridiculously [[LargeHam hammy]] performance from Andrew Sachs) and the 2012 novelisation, which makes him androgynous and unexpressive as well as fleshing out his backstory and personality a ''lot''.
* SpotOfTea
* TheImmodestOrgasm: In the book, Skagra's ship apparently ''really likes'' time travel.
* WeirdnessCensor: Professor Chronotis has been living in the same set of rooms at Cambridge (actually his TARDIS, which is '''even more''' out of date than the Doctor's) for ''centuries''. According to him everyone at the old Cambridge colleges are very discreet, that and a perception filter.
** There is also a RunningGag in the book that everybody, including the Doctor, instantly dismisses any negative or suspicious thought they have about Chronotis by deciding that he is just a "nice old man". This is strongly implied to be the result of a low-key use of his powers.
* WhatWeNowKnowToBeTrue:
-->'''The Doctor''': What? Do you understand Einstein?\\
'''Parsons''': Yes.\\
'''The Doctor''': What? And quantum theory?\\
'''Parsons''': Yes.\\
'''The Doctor''': What? And Planck?\\
'''Parsons''': Yes.\\
'''The Doctor''': What? And Newton?\\
'''Parsons''': Yes.\\
'''The Doctor''': What? And [[TheLastOfTheseIsNotLikeTheOthers Schönberg]]?\\
'''Parsons''': Of course.\\
'''The Doctor''': You've got a lot to unlearn.
[[Creator/TomBaker SHAAAAADAAAAAA!!]]