The confusing one.
To make a long story as short as humanly possible, the Doctor takes companion Ace back in time to Victorian Britain for some form of training that involves facing her childhood fears. The TARDIS lands in a mansion of the era, and the Doctor and Ace soon find themselves the guests of a "Josiah Smith" who proudly proclaims the wonders of the Darwinian concept of evolution. Ace, who has a trauma involving haunted mansions, tells the Doctor that she doesn't appreciate his lesson. Also, there is a Rev. Ernest Matthews, who despises evolution, there's a maid service that refuses to stay in the house after 6pm... and a polite, well-dressed Neanderthal butler named Nimrod. The maid service is apparently also taking care of Great White Hunter named Redvers Fenn-Cooper, who has recently lost his mind by "seeing something he cannot comprehend". And there's a sinister housekeeper, and Josiah's niece who isn't entirely uncreepy herself. Ace decides to crossdress for the occasion (mainly because her modern clothes including Vapor Wear cause people to call her a shameless trollop).
Still with us? As the story unfolds at a breakneck pace, it's soon revealed that the disturbingly creepy house might be haunted. Only it's not. It's the base for an alien surveillance force full of animated alien insectoid husks, the leader of which (Josiah himself) wishes to integrate themselves with the human race. In his opinion, that's best done by having Fenn-Cooper assassinate Queen Victoria and taking over England as its new King, as that's how evolution works in his mind.
The Doctor and Ace soon stumble across the fact that Josiah is not the leader of the expedition — that's another being, who's being held prisoner within his own ship, which is currently beneath the mansion. This being is, best put, an Angel (not a weeping one, thankfully) going by the name of "Light". Light is dismayed to find himself back on Earth, particularly at the fact that everything has changed. He was just done cataloguing the whole thing when evolution just had to go and render all his work invalid. Then the Doctor talks to exotic bugs for a bit and wakes up a policeman who was locked in a drawer in suspended animation. As other plot threads, which include a commentary on evolution itself, as well as a lovely side-discussion of Java, resolve themselves very rapidly, Light essentially suffers from a blue screen of death as he comes to the realization that change sucks. His answer to all this change? Utterly eliminate all life on Earth using actual primordial soup. They all discuss this over a nice dinner party while Ace, caught up in yet another plot thread, teaches an alien named Control how to be a lady.
The story finally comes down to the Doctor and Light having a verbal sparring match — the Doctor finally talking Light into ending his own life so that he will no longer change. The space ship beneath the mansion decides to recruit a new crew, and enlists Control, who was formerly locked within the ship with fellow prisoners Light, Fenn-Cooper and Nimrod. Ship and crew then depart for places unknown while the Doctor talks to Ace about any regrets she may have in her life.
As it turns out, Ace encountered this place in her youth (in the future, with respect to the story's Victorian setting) and the evil feeling left behind from Josiah and Light pushed Ace into burning down the mansion. This resulted in a trauma as well as some time spent with meddling guidance counsellors. Ace's only regret after all this? That she didn't blow it up instead.
If you didn't follow any of that, don't worry. The script was already considered too long for the traditional four part story and was then compressed to three parts for budgetary reasons.
The original pitch was set in a sinister house from the Doctor's childhood, on Gallifrey, but showrunner John Nathan-Turner asked for that aspect of it to be changed, as he felt it gave away too much about the Doctor at once. Marc Platt went on to actually write that story as the notoriously confusing Doctor Who New Adventures Grand Finale Lungbarrow. "Ghost Light" ended up being the final production of the original series, as it was produced after "The Curse of Fenric" and "Survival", despite airing before both of them; they got priority in the production scheduling because they required extensive location filming. note
The DVD release contained a 45-minute documentary, a 30-minute interview and commentary that slowly filled in the gaps in what was missing and not entirely clear.
- Archive Panic: Invoked in-canon. Light gets a severe case of this when he tries to catalogue all of Earth's life forms.
- Arson, Murder, and Jaywalking:
- When it becomes clear for the Doctor that his presence is not quite liked:The Doctor: Let me guess: my heresies appall you, my theories outrage you, I never answer letters, and you don't like my tie.
- Then there's this exchange during dinner.Josiah: I can provide a new order. Wealth! Prosperity!Doctor: Confusion, wastage, tyranny, burnt toast!
- When it becomes clear for the Doctor that his presence is not quite liked:
- Artistic License – History: Josiah plots to overthrow Queen Victoria and seize the throne for himself thereby, it's explained, becoming rulers of the most powerful country in the world. The only problem with this plan is that Victoria was a powerless symbolic figurehead. The British monarch has not attempted to veto a Bill of Parliament since Queen Anne and has not appointed a government that did not have the confidence of Parliament since King William IV. The first example may be justified by him being very stupid and over-confident.
- Audience Surrogate: One of the ways they were trying to develop Ace around this time was to have The Doctor teach her about the universe so she could take a more active role in their adventures than previous companions had. This meant that in this story, The Doctor doesn't spend much time explaining things to her; it's explicitly stated that he's "testing" her. But as Andrew Cartmel admits, this unfortunately meant that a lot of things don't get explained at all, and that they probably should have had someone like Inspector Mackenzie be the audience surrogate. (Although with their time constraints it still might not have made things much clearer.)
- Artistic License – Biology: Josiah and his laughably inept grasp of evolutionary theory, though the former trope name (You Fail Biology Forever) could just as easily be the arc word for the serial as a whole, seeing how it skewers both Light's attempts to catalogue a neverending list of lifeforms and Victorian England's attitudes towards evolutionary science juxtaposed with their own rigid social hierarchy.
- Bifauxnen: Ace in Victorian men's clothes.
- Big Eater: Inspector Mackenzie, much to the Doctor's annoyance:Since I awoke you, you have consumed three English breakfasts, two elevenses and one four-course meal. Why don't you go and get Mrs Grose to make you some afternoon tea.
- Body Horror: Reverend Matthews slowly turned into an ape. Another example:Light: (holds up a bloody, severed arm) "I wanted to see how it works, so I dismantled it."
- Brainwashed and Crazy: Gwendoline kills several people while under the influence of Josiah's mind control. The Doctor notes, however, that although Josiah was responsible for her actions, he wasn't responsible for how much enjoyment she got from carrying them out.
- Bond One-Liner: After talking Light to death, the Doctor remarks: "Subject for catalogue: File under imagination, comma, lack of."
- Brandishment Bluff: The Doctor holds Josiah hostage with his radiation detector, which looks just enough like a gun to do the job.
- Camp: Light, the angelic Sealed Evil in a Can
- Cat Fight: Ace and Gwendoline. Twice.
- Changed My Jumper: Redvers Fenn-Cooper tells Ace that she's barely dressed, and later, Reverend Ernest Matthews is shocked at the Doctor "parading [his] shameless wantons", so the Doctor sends her off with Gwendoline to get something more suitable for Victorian England. It doesn't work the first time...
- Contemporary Caveman: The Doctor and Ace confront a talkative, very polite Neanderthal named Nimrod used as a butler.
- Continuity Nod:
- Creepy Housekeeper: Oh yes, and does she have a secret.
- Devolution Device: Rev. Matthews is turned into a monkey by a Light; it is justified, however, by suggesting that this is not "de-evolution" as such, because the alien could have turned him into anything and only chose the monkey form to mock the clergyman's anti-Darwinist beliefs. (Another character, for instance, is transformed into stone instead.)
- Don't Wake the Sleeper: Nimrod refers to Light as the "Sleeping One" who must not be woken.
- Evil Tainted the Place: Even after the creepy occurrences in Gabriel Chase have been explained (well, sort of) by the story, in the events still leave a sense of evil and creepiness about the place which inspires Ace to burn it down in the future.
- Expy: Redvers Fenn-Cooper was based on Alan Quartermain.
- A Form You Are Comfortable With: Light is not really an angel, or even humanoid; that's just the form he's "naturalised into".
- Gambit Pileup: The conflicting plans of Light, Control, and Josiah get pretty complicated, to the point that The Doctor exclaims, "Oh, things are getting out of control, even I can't play this many games at once!"
- Go Mad from the Revelation: Redvers Fenn-Cooper was unlucky enough to witness Light's sleeping form in the cellar of a Victorian mansion. The experience turned his hair white and drove him into the depths of insanity. By the time the Doctor arrives, he's disassociated his own identity so well that if he does acknowledge his own name, it's in the third person.
- Gorgeous Period Dress: Like "Black Orchid" before it, "Ghost Light" is a fine exemplar of a subclass of Who stories: the let's-raid-the-BBC-wardrobe-department serial.
- Ham-to-Ham Combat: Just name someone who isn't chewing the scenery in this episode. Now realize that all of the scenery-chewing just plain makes the adventure even more awesome.
- Haunted House: Ace recalls having visited one, and resolving never to go there again. That house was Gabriel Chase, a hundred years after the events of this episode.
- Kindly Housekeeper: The daytime housekeeper fits this trope to a T, hitting all the checkmarks on it. She won't stay past 6pm though, because no one in their right mind would be there then. Which should tell you almost to the second when the TARDIS arrives.
- Let the Past Burn: Ace tried to invoke this by burning down Gabriel Chase. She wasn't counting on the Doctor bringing her back in time to before she did it.Ace: When you're a kid you smash things you hate. But what do I do if it keeps coming back?
- Light Is Not Good: Light wants to kill everyone and everything, because we keep changing and that's just confusing.
- Like a Duck Takes to Water: Nimrod the neanderthal adjusts pretty well to being a butler, and later an interstellar explorer.
- Mind Screw: "Ghost Light" has gained a reputation as one of the most incomprehensible Doctor Who episodes ever. Even being level with some episodes written by Steven Moffat.
- Names to Run Away from Really Fast: Subverted in the case of Nimrod the Neanderthal butler, who is probably the nicest character in the serial.
- Nice Job Breaking It, Hero!: The Doctor frees Light believing that he can stop Josiah... not realising that he's trading from a fairly pathetic guy who wants to take over the British Empire to a full-blown Omnicidal Maniac.
- Noble Savage: The Doctor claims Ace is this to excuse her scandalous clothing.
- Noodle Incident: In a deleted scene, the Doctor mentions that he once imprisoned in Newgate and that it took him three weeks to escape.
- Obstructive Bureaucrat: Light is a godlike bureaucrat known only as Light: having made a comprehensive survey of life on Earth many millions of years ago, he retires to stasis - only to awake in the nineteenth century and discover that evolution has made all his work invalid. His proposed solution is to sterilise the planet of all organic life and prevent any further amendments to his catalogue.
- Our Angels Are Different: Light.
- Police Are Useless: Inspector Mackenzie is a stereotypical flat-footed cop who spends all his time gorging food and impotently trying to impose his authority on everyone around him.
- P.O.V. Cam: Used to show the Reverend Matthews'... departure.
- Right on the Tick: The house's inhabitants come to life when the clock in the hall strikes six. (The Doctor lampshades the fact that it's not When the Clock Strikes Twelve.) When the Doctor's plans come to fruition a little early, he puts the clock on by a quarter of an hour so they're all there to see it happen.
- Screw the Money, I Have Rules!: Josiah tries to get the Doctor on his side by offering a bribe of £5000. He fails.
- Q: "Who was it who said Earth men never invite their ancestors round for dinner?" A: Douglas Adams, author of The Hitchhiker's Guide to the Galaxy, former script editor for Doctor Who and author of such episodes as "The Pirate Planet", "City of Death", and the sadly unfinished "Shada".
- Mrs Grose, the day housekeeper, is a reference to the character of the same name in The Turn of the Screw.
- Inspector Mackenzie shares his name with the antagonist of the Raffles stories.
- The subplot with Control's desire to be "a ladylike" contains many shout-outs to Pygmalion. The Doctor even calls Ace "Eliza".
- Redvers Fenn-Cooper's surname may be an allusion to James Fenimore Cooper.
- Ace compares Josiah's aversion to sunlight to Dracula, and tries the old pull-back-the-curtain trick on him (unfortunately just after he'd levelled up and lost that weakness).
- When the Doctor is messing with Light by listing mythical creatures that Light "missed" when he catalogued Earth's lifeforms, he throws in a couple of the creatures from Lewis Carroll's poem "Jabberwocky".
- Shut Up, Hannibal!: Josiah Smith is explaining how he will rule the British Empire after he's assassinated Queen Victoria:Josiah Smith: The British Empire's an anarchic mess. There's no clear directive from the throne, no discipline. Result? Confusion, wastage. I can provide a new order. Wealth, prosperity...The Doctor:... confusion, wastage, tyranny, burnt toast, till all the atlas is pink (hums Rule Britannia and salutes.)
- So Was X: Or in this case, So Am I.Josiah: I'm as human as you are.
- Sufficiently Advanced Aliens: The Doctor, obviously, but also Light, Smith, Control and Nimrod.
- Summon Bigger Fish: The Doctor's plan to deal with Josiah, with quite disastrous results.
- Taken for Granite: Gwendoline and her mother. In what turned out to be the last scene ever filmed for the original series, bringing an extra dimension to the words "Well... you'll never change again."
- Talking the Monster to Death: Light is infuriated by the fact that the Earth has changed, making the inventory he was working on meaningless. He resolves to destroy the Earth so it will stop changing. The Doctor points out the idiocy of thinking that you can stop change, and that everything in the universe is changing, including Light. Light commits suicide because he considers change a Fate Worse than Death.
- Taxidermy Terror: Ace gets trapped in a room full of this, and freaks out.
- Tempting Fate:
- "While we have the lamp, we're safe!"
- "Nonsense, young lady. That thing isn't dangerous."
- Third-Person Person: "Poor Redvers... his hair turned white."
- Viewers Are Geniuses: Any scenes where the plot stopped for people to explain what was going on were excised in the editing stage because there genuinely wasn't enough running time in which to fit any of them in, resulting in great swathes of plot that are never actually explicitly explained within the story at all and thus have to be put together by the audience themselves. Considering how complicated the plot is in the first place, this task proves easier said than done.
- Waxing Lyrical: The Doctor says it's been a hard day's night.
- What the Hell, Hero?: Ace was horribly traumatised by the creepy atmosphere of the mansion in her own time, so the Doctor decides to take her back to find out what happened without informing her beforehand. She is obviously somewhat upset about this.