[[quoteright:350:http://static.tvtropes.org/pmwiki/pub/images/unearth_3880.jpg]]
[[caption-width-right:350:And thus, a SciFi dynasty is born...]]

->''"If you could touch the alien sand, and hear the cry of strange birds, and watch them wheel in another sky, would that satisfy you?"''
-->-- '''The Doctor''', Part Two - "The Cave of Skulls"

We commence with the World's Trippiest TitleSequence and the first time an audience would hear the "Oooh-ee-oooh" of the theme tune. (Don't believe us? [[http://www.youtube.com/watch?v=75V4ClJZME4 watch this]] (with about two minutes worth of unused footage).)

Two teachers, Barbara Wright and Ian Chesterton, think their super-bright pupil, Susan Foreman ([[Music/VanMorrison a brown-eyed girl, complete with transistor radio]]), is a bit on the strange side. She's bored with regular physics and math and wants to move on to multidimensional physics and maths, and she thinks that the UK has decimalised its currency (which hasn't yet happened in 1963: Britain would decimalize the pound in February 1971, after a few years of preparation. Amusingly, at the time this serial aired, pretty much all of the rest of the Commonwealth had either already decimalised, like South Africa, or was in the process of doing so, like Australia and NZ). So, they decide to follow her home one night. This being 1963, it's benign concern for the welfare of a child, and [[ValuesDissonance not at all creepy]].

They arrive at Susan's home address of 76 Totter's Lane. It's a junkyard. They hear Susan's voice coming from inside a police box. Thinking that her grandfather, "I. M. Foreman", has locked her in there, they proceed to open the door and enter the TARDIS. Which is bigger on the inside than out. Her grandfather, a crotchety old man, is the Doctor.

Deciding that he can't have them tell the world about the CoolShip and that the "Foremans" will need to leave the 1960's again, he starts up the TARDIS, acquiring the first two companions via abduction. Ian and Barbara are knocked unconscious by the time travel.

When they've landed again, the foursome step out of the TARDIS and Susan quickly exposits that it was supposed to have changed shape: the first clue that it's somewhat less than reliable. Before long, the Doctor is kidnapped by a tribe of cavemen when they see him smoking his pipe [[EarlyInstallmentWeirdness which he never smokes again]]. This tribe has lost the ability to make fire, and the Doctor agrees to placate them by giving them fire, but unfortunately he has lost his matches. His three companions try to rescue him, but only succeed in getting themselves captured too. In the middle of all that, the Doctor decides to simply kill a friendly but wounded cavemen who's slowing them down a bit. This earns him his first ever WhatTheHellHero from Ian, who prevents the murder. The tribe of primitive humans with monolithic names keep their captives in a cave full of skulls, skulls that have been obviously split open. Charming.

A friendly (well, less hostile) tribesperson unties them, and they make tracks. Eventually, the Doctor tricks the hostile aspiring caveman leader into admitting he's a murderer, Ian gives the less hostile aspiring caveman leader the gift of fire, and they all escape back to the TARDIS. But since they had to take off in a hurry on account to avoid being speared, the Doctor was unable to make the calculations necessary to chart a course back to 1963. Hopefully their next landing spot will be a bit less eventful...

NB: This story is commonly also called "100,000 BC", and less commonly called "The Tribe of Gum". "An Unearthly Child" is the title of the first episode (episodes were individually named until season 3), but the DVD also gives the name to the entire story, as did the Target Books novelisation, so "Unearthly Child" is now considered the official BBC-sanctioned title for the story.

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!!Tropes

* AccidentalMisnaming: Ian is known to the tribe as "Friend".
* ActionGirl: Susan attacks one of the cavemen with a rather disturbing enthusiasm.
* TheAllegedCar: After they arrive in pre-history, Susan expresses shock that the TARDIS still looks like a British police box. Its Chameleon Circuit is broken.
* AllThereInTheManual: According to the novelisation, The Old Mother is said to be the mother of Za. The father of Za is named Gor.
* ArrangedMarriage: Horg says his daughter will marry the Chief of the tribe. With Za it seems a PerfectlyArrangedMarriage.
* BigBad: Kal, the first in a long line of ''Doctor Who'' villains and the person responsible for its first two deaths before becoming the third.
* ButterflyOfDoom: The Doctor is so paranoid about the possible ramifications of this trope that he is convinced that the mere idea that a device such as the TARDIS exists could irreparably change the course of human history.
* CarpetOfVirility: Kal.
* CharacterizationMarchesOn: In one episode, the Doctor -- y'know, the poster boy for [[TechnicalPacifist Technical Pacifism]] -- is apparently prepared to bash a helpless man's head in with a rock... because Barbara's insistence on caring for his wounds is slowing them down as they try to escape. In general, the Doctor is kind of a dick for the first twelve-and-a-half episodes of the show, before he softens up at the end of "The Edge of Destruction", which is pretty off-putting to viewers who have the benefit of fifty years' worth of lore about the character.
** The Franchise/DoctorWhoExpandedUniverse also has many, many theories on how this is precisely the moment that started his love for humans, realising how they kept him from slipping into villainy.
* {{Cliffhanger}}: The very first ''Doctor Who'' example, and it's a good one. The TARDIS has appeared on a mysterious, desolate plain... and an ominous shadow creeps into view downstage of it.
* DamselInDistress: Barbara in the last two episodes.
* DeadpanSnarker: Horg.
* EarlyInstallmentWeirdness:
** In the unaired first version of the episode (dubbed the "pilot" version, but not a {{Pilot}} in the modern sense), the Doctor appears even ''more'' belligerent and sinister, including actively berating Susan for leading Ian and Barbara back to the TARDIS. Susan also acts and dresses older and more "unearthly". Then there's Susan's reference to coming from the 42nd century, a background element which was abandoned. The TARDIS also doesn't make its distinctive "wheezing and groaning" yet when they travel back in time. Interestingly though, some other details in the pilot sound ''more'' like the Gallifrey eventually established a few years later - the broadcast version is much more vague about their origins.
** Episode 2 shows the Doctor smoking a pipe. This is the only on-screen occasion in which he is ever shown smoking; hereafter he is a non-smoker. (The smoking is plot-justified in this case as it propels the firemaker plotline.) Also, the Doctor's justification for taking Barbara and Ian captive was the apparent danger in allowing knowledge of things like aliens and the TARDIS to fall into contemporary human hands. He'd then spend the next fifty years taking humans as companions and telling them (both those taken as companions and those not) about things like aliens and the TARDIS.
** When the TARDIS dematerialises for the first time, both Ian and Barbara faint. This effect is unique to this story as Ian and Barbara show no further ill effects in subsequent dematerialisations (at least not of this nature and not caused directly by the TARDIS activating), nor do any future new TARDIS passengers.
* EstablishingCharacterMoment: The First Doctor acting like a senile old man to his future companions. Barbara is introduced being neurotic about a girl in her class. Ian is introduced supporting her and suggesting a plan of action. Susan is introduced alienating everyone around her and dancing to pop music coming from a strange futuristic radio.
* FamilyUnfriendlyViolence: The oft-quoted truism that Doctor Who was originally supposed to be an educational programme for children seems somewhat dubious in light of this story. There are a lot of dark, violent themes and moments, such as the sight of Za's slashed up, bloody chest after an animal attack, the Doctor trying to smash open the head of an injured man and the heroes being trapped in a cave full of broken skulls, foreshadowing their possible fate. The most shocking part is a lot more subtle, as Ian and Barbara's attempt to get a policeman, and in particular their fear of what the Doctor might be doing to Susan in the mysterious blue box imply that they (wrongly) fear he may be molesting her.
* FlamingSkulls: The Doctor's group escapes by scaring the cavemen by placing skulls inside a fire he has started.
* FutureImperfect: What draws the teachers' attention to Susan. Susan mixes up a question about British currency, due to forgetting she's in a time period before it switched to a decimal system. (This did indeed happen.)
* HardToLightFire: The plot is driven by the fact that the Tribe of Gum no longer knows how to make fire.
* HumansThroughAlienEyes: "Before your ancestors invented the wheel my people had made time-and-space travel into child's play!"
* IdiotBall: The Doctor carries it in episode 2. Despite being from an advanced civilisation that has mastered time travel, and himself being a scientist, the Doctor appears to only know how to make fire using matches and not any number of other methods boy scouts have been using for generations to create flame. (A possible rationalization is he's playing dumb out of concern he might introduce fire too early to earth civilisation, even though he's within earshot of cavepeople speaking openly about fire, meaning it isn't an unknown concept.
* InsultToRocks:
-->'''Ian:''' "You're treating us like children!"\\
'''The Doctor:''' "Am I? The children of ''my'' civilisation would be insulted."
* LineOfSightName: It is implied that Susan got her last name from the junkyard where she and her grandfather were hiding out.
* MoreThanThreeDimensions: Discussed briefly, demonstrating how strange Susan Foreman is. Worth noting that she's supposedly a [[AdorablyPrecociousChild 15-year-old girl]] at this point.
-->'''Susan''': ''[About a math problem]'' It's impossible unless you use D and E.
-->'''Ian''': D and E? Whatever for? Do the problem that's set, Susan.
-->'''Susan''': I can't, Mister Chesterton. You can't simply work on three of the dimensions.
-->'''Ian''': Three of them? Oh, time being the fourth dimension, I suppose? Then what do you need E for? What do you make the fifth dimension?
-->'''Susan''': Space.
* {{Mundanger}}: The menace in the first ''Doctor Who'' story? ''Politics''.
* NamesToRunAwayFrom: Kal.
* NeverMessWithGranny: The oldest cavewoman is also the most vicious, and the most politically adept schemer.
* NotThatKindOfDoctor: When the Doctor is refusing to help Ian and Barbara administer first aid to the wounded Za, Barbara points out that he's a doctor, and he says that he isn't a medical doctor.
* OneMillionBC: An alternate title for this story is "100,000 BC".
* ScreamingWoman: Justified in the case of Susan; she's incredibly sheltered and repeatedly shown to be nervous and easily intimidated, and has been raised by the Doctor to view the outside world as an inherent threat. And, of course, she's also a ''child''; younger [[ReallySevenHundredYearsOld by Gallifreyan standards]] than human ones, and even a shy human teenager could be forgiven for screaming while being kidnapped by cavemen.
** It could be argued that applying this trope to Susan is unfair; she screams quite often, but is also shown to be remarkably intelligent, perceptive, and generally a very useful person to have around. She just gets excited from time to time.
* ShakyPOVCam: Used to represent the jungle cat that attacks Za.
* StyrofoamRocks: Naturally, as the whole thing was filmed in a studio (and really looks it).
* TheTheTitle: Individual titles for each episode mean that we get "The Cave of Skulls", "The Forest of Fear" and "The Firemaker". Also, "The Tribe of Gum" was a working title (although the naming convention used in those early days would have properly named it "Doctor Who and the Tribe of Gum")
* TitleDrop:
** Ian addresses the Doctor as "Dr. Foreman"; the Doctor responds, "Eh? [[ThrowItIn Doctor who]]?" With that, a half-century RunningGag heard its starting gun.
** Then, later, Ian to Barbara: "Who is he? Doctor who? Perhaps if we knew his name, we might have a clue to all this."
* WhamShot: The first time we see what's inside that tiny police box.
* WhatTheHellHero: Ian calls the Doctor out for his aforementioned attempted rock bashing.
* WritersCannotDoMath: What is clearly supposed to be the quadratic formula is seen on a chalkboard in the background. However, the denominator is written as 2ab instead of the actual 2a.
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