History Recap / DoctorWhoS36E10TheEatersOfLight

The one where popcorn saves the day.

* ArtisticLicenseHistory:

** Bill, like Amy and Rory, has a love and knowledge of the Romans. The Doctor himself saying that he should know more because he made Roman history is a reference to both his and his current face's previous adventures there.

* {{Fainting}}: Bill passes out after the monster's attack leaves black slime on her neck.

Written by Rona Munro, who previously wrote "[[Recap/DoctorWhoS26E4Survival Survival]]", the final serial of the original run of ''Doctor Who''. With this episode, she became the first person to write for both the old and the new television series (and in all likelihood, the only one, given that most of the other Classic Series' writers by this point were either retired or dead).

Written by Rona Munro, who previously wrote "[[Recap/DoctorWhoS26E4Survival Survival]]", the final serial of the original run of ''Doctor Who''. With this episode, she became the first (and, in all likelihood, only) person to write for both the old and the new television series.

** A Roman soldier identifies being attracted to both men and women as being "normal", and is nonplussed about a comrade of his being exclusively attracted to men. Though not quite as dogmatic about it as other cultures in history, Romans were generally still a bit prudish when it came to male homosexuality. A man who professed an exclusive preference for other men would, among other things, be ineligble for political office and be considered an outlaw.

Written by Rona Munro, who previously wrote "[[Recap/DoctorWhoS26E4Survival Survival]]", the final serial of the original run of ''Doctor Who''. With this episode, she became the first person to write for both the old and the new series.

*** These same soldiers are readily accepting of Bill's lesbianism, and seem confused that she thought they would object. Romans generally found lesbianism (as they understood it) ''very'' objectionable, and stereotyped lesbians as hedonistic rapists.

* UsefulNotes/BritishWeather:
** When the Doctor finds a Roman corpse and notes that the signs of death are consistent with total deprivation of sunlight, Nardole quips "Death by Scotland!"
** Possible ActorAllusion re the withering look Twelve gives Nardole before replying with a terse, "No." Peter Capaldi is Scottish (Rona Munro is as well).

-->'''Lucius:''' There are painted barbarians up there. They outnumber us. There is a beast of darkness that laid waste to an entire legion in less than an hour. No one man can make a difference to that.
-->'''Bill:''' Maybe that's what you don't learn when you think it takes five thousand highly trained soldiers to slaughter a bunch of Scottish farmers. Yes, one man can. And he's here.

-->'''The Doctor:''' For now, would you mind awfully all just jumping out of your skins and allowing Nardole and I to escape in the confusion?
-->'''Kar:''' WhoAreYou
-->'''The Doctor:''' Let me explain. ''[bag of popcorn he'd tossed into the fire begins popping loudly, the Doctor and Nardole run while the Picts are starting at the noise]''

* SciFiWritersHaveNoSenseOfScale: The exact time dilation caused by the portal is unclear, but it's unlikely that the soldiers would be able to hold the gate for long. It's estimated that it would take anywhere from three hours to a week to bring them up to the present day. Assuming they don't get instantly swarmed and can still face the monsters one at a time, that would still be a difficult task. They plan to hold the gate until the sun dies, which is simply impossible—even in the best case scenario, they would need to last over nine and a half thousand years in order to reach the year five billion (which is the estimated time the sun will burn out).

-->'''Doctor''': There were strangers at the door, and a guard dog in the attic.

* BiTheWay: The Romans see this as the default, and think it's slightly old-fashioned to be attracted to only one gender.

* TranslatorMicrobes: Bill figures out this is in effect when she asks Simon how he speaks English and he responds by accusing her of speaking Latin, finally realizing this is why she's been able to understand everyone on her space adventures. It also allows the Picts and Romans to understand one another when they meet in the Doctor's presence.
** Bill is the first companion to comment on the fact that the translation field also makes people's lip movements appear to sync up with the translation of what they're saying.

* ScreamingWarrior: On first seeing Bill, Kar screams and charges at her with a sword. Bill flees only to fall down a hole [[ShaggySearchTechnique and find the Roman soldier she's been looking for]].

* GrimUpNorth: When the Doctor finds a Roman corpse and notes that the signs of death are consistent with total deprivation of sunlight, Nardole quips "Death by Scotland!"
** Possible ActorAllusion re the withering look Twelve gives Nardole before replying with a terse, "No." Peter Capaldi is Scottish (Rona Munro is as well).

-->'''The Doctor:''' Let me explain. ''[tosses bag of popcorn into the fire, then runs while the Picts are starting at the noise]''

** "Villains" that aren't actually evil: Bill and the Doctor both point out that both sides of this war are scared and just defending their homelands, and they end up joining forces to defeat the greater threat. The Pictish Beasts themselves are merely hungry; it's just that their food source is something this dimension needs to exist, much less survive.

* EnergyAbsorption: The monster feeds on all forms of light. It can even suck the light from living things, desiccating them.

* {{Fainting}}: Bill's reaction to discovering she's got black slime on her.

Escaping and investigating a nearby cairn, the Doctor comes to realize that this creature feeds upon sunlight and anything that contains it -- including humans. It comes from another dimension via a portal hidden in a cairn; it lies beyond a gate that opens for a few moments with every sunrise. Kar is the latest Keeper of the Gate, in fact, tasked to keep the creature from emerging by fighting it back -- but she was desperate to stop the Roman invaders and sicced it upon them. Alas, having not fed for a long time, its hunger is ravenous. If it cannot be forced back to from whence it came, it ''and'' its kin will ravage this dimension until not a star is left in the universe. The Doctor has a plan, but it will require both the surviving Romans and Pictish to join forces... and something more besides, something he's not willing to tell Bill...

* TheForeverWar: The ultimate fate of the Picts and Romans is to fight the beasts beyond the gate for as long as they live.

* ScreamingWarrior: On first seeing Bill, Kar screams and charges at her with a sword. Bill flees only to fall down a hole [[ShaggySearchTechnique and find the Roman soldier she's been looking for]].

* CleverCrows: The crows here can speak, to Nardole's surprise -- and they're calling the Doctor's name! The Doctor explains that crows have always been able to talk but got grouchy over millennia and that's why they don't sound like anything anymore... or so he thinks. It turns out that the crows learn and say ''Kar'' to remember her HeroicSacrifice forever more. Had the Doctor gone through with ''his'' intended HeroicSacrifice, they would still say his name. (This is paralleled by the Doctor's TARDIS appearing in the drawing on the standing stone at the beginning, but it being replaced by her and the Roman legionaries at the end.)

* TranslatorMicrobes: Bill [[GenreSavvy figures out]] this is in effect when she asks Simon how he speaks English and he responds by accusing her of speaking Latin, finally realizing this is why she's been able to understand everyone on her space adventures. It also allows the Picts and Romans to understand one another when they meet in the Doctor's presence.

->''"Now you have a choice. You can all keep on slaughtering each other till there’s no one left standing, or you can '''''grow the hell up!'''''"''

** Bill talks about how she learned about the mystery of the Ninth Legion from a book, most likely the famous historical novel ''Literature/TheEagleOfTheNinth'' by Rosemary Sutcliff.[[note]]There are [[LostRomanLegion many other books inspired the mystery]], but most offer SF explanations like "they were transported to another world" and are unlikely to be the source of Bill's conviction that the Legion was undone by mutiny.[[/note]]

** TheTriple: He's also [[NoodleIncident governed, farmed and juggled]] in Roman Britain.

* InformedAbility: The titular creatures are never shown eating light, except for a throwaway comment about "eating the light from their bodies". Additionally, the Doctor has never seen the creatures before yet he deduces that they will eat the sun and all the stars if freed despite no evidence for this being presented in the episode. In fact, sunlight is stated to be a ''cure'' for the slime that got on Bill's neck.

* LongLastLook: Lucius to Bill as he goes through the portal.

* SciFiWritersHaveNoSenseOfScale: The exact time dilation caused by the portal is unclear, but it's unlikely that the soldiers would be able to hold the gate for long. It's estimated that it would take anywhere from three hours to a week to bring them up to the present day. Assuming they don't get instantly swarmed and can still face the monsters one at a time, that would still be a difficult task. And they plan to hold the gate until the sun dies, which is simply impossible—even in the best case scenario, they would need to last over nine and a half thousand years in order to reach the year five billion (which is the estimated time the sun will burn out).