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is a Middle Grade / Young Adult
subterranean fiction series by Roderick Gordon and Brian Williams. The series consists of six books. A manga based off the books was released in Japan, and film rights have been given to Vincenzo Natali
, though production has never started
Will Burrows is a fourteen-year-old boy whose major passion is digging. He often helps his archaeologist father perform excavations in the rural British town of Highfield. However, he gets more than he bargained for when his father's latest investigation leads to the discovery of an underground civilization called the Colony. The Colony has long existed hidden from the "Topsoilers" on the surface. However, the tyrannical Styx ruling class of the Colony has come up with a plan to commit genocide on the Topsoilers and reclaim the surface for themselves. Because Adults Are Useless
, it is up to Will and various friends of his to stop the Styx, a quest that takes them ever deeper into bowels of the Earth.
- Tunnels (2007). Originally published as The Highfield Mole: The Circle in the Spiral in 2005. The earlier edition was self-published and few copies were actually sold.
- Deeper (2008).
- Freefall (2009).
- Closer (2010).
- Spiral (2012).
- Terminal (2013).
This series includes examples of:
- Aborted Arc: the Dominion plot was simply forgotten after the end of Closer. Arguably it becomes unimportant due to the events of Spiral, but there was simply no mention of it whatsoever.
- Absent-Minded Professor: Dr. Burrows in spades. Also Will has picked up a little of this from his foster father.
- Action Bomb: In Spiral, the Styx use the Dark Light to brainwash people into being action bombs.
- Action Girl: Elliott
- Adults Are Useless: Played straight with the Burrows parents, but pretty well averted below-ground. For a story with kids as the protagonists, there are a surprising number of competent adults. Most of the antagonists are adults, and they are quite good at their jobs.
- Will's parents turn out to be a brutal justification; they were both Darklit continuously by the Styx to make them that way.
- Advanced Ancient Acropolis: Dr. Burrows finds bits of evidence hinting that there was once a civilization that knew deep secrets about what lay far within the Earth. Turns out they had discovered the Garden of the Second Sun. And then there's yet another apparent lost civilization within the Garden, which is revealed in Terminal to be the command center for a Planet Spaceship—the Earth itself.
- Adventurer Archaeologist: Dr. Burrows thinks of himself this way.
- Alien Among Us: Well, the Styx turn out to be no more alien than us, but they still have a definite Aliens Among Us feel until we find out all life on Earth, Styx and weird monsters from the Deeps included, are all from the same planet.
- Alien Geometries: The crystal belt. There are hints that the place may even have wildlife.
- Aliens In Highfield: Bonus points every time a character says "But this is Highfield!" And the Styx aren't just another sentient race that happens to inhabit Earth; they're actually aliens...well, sort of.
- Ancient Astronauts: At first, Will and friends think they've found evidence that aliens visited Earth in the distant past. Turns out, that never happened. They were on Earth the whole time—they built Earth.
- Ancient Conspiracy: There's more than one. First, that a group of people have been living beneath Highfield for quite a long time, with help from their secret comrades on the surface. Second, that the Styx are trying to destroy Topsoil civilization and have manipulated it for hundreds of years. Third, the Styx are aliens who look like their hosts and can go through a deadly Phase to kill off any threat to their species, and they're about to do it to humans. Fourth, there's a hidden world in the center of the Earth where all the missing links in evolution and countless living fossils exist, and ancient civilizations knew about it. Fifth, the Styx aren't really aliens at all, but Abusive Precursors who constructed Earth as a Planet Spaceship; they're no more alien than us. Wow.
- Anyone Can Die: No one is safe.
- Badass: Drake, most prominently, though most of the Old Guard could be considered this.
- Sweeney and Jiggs, for instance, are respectively an incredibly muscled supersoldier and a skilled assassin who kill multiple Limiters with little more than their bare hands.
- And Then John Was a Zombie: Elliot's Styx side becomes much more apparent in Spiral and Terminal, until she even grows insect limbs during the closing moments of the series. And then afterwards the final moments of Terminal strongly imply that Will himself may be becoming a Styx.
- Apocalypse How: Genetically engineered super-virus, that's how. When that plan gets tossed out the window, they switch to "turn into giant bugs and raise an army of hellish Nigh Indestructible shape-shifters."
- Atlantis: At one point, while wildly speculating to himself, Dr. Burrows believes he's found ruins left by refugees from Atlantis.
- Badass Normal: Well over half the human cast.
- Beauty Equals Goodness: You can tell Tom Cox is the bad guy by the giant ("melon-sized") tumors on his face.
- Big Creepy-Crawlies: The first we see is Dr. Burrows' dust mite the size of a small car. Elliott calls them cave cows. Later on we get similarly-sized "spider monkeys" and Brights. In Closer, we even get huge fleas, which are normally scavengers but are totally okay with eating you alive. And the female Styx turn into these during the Phase, with insect limbs exploding out of their backs and ovipositors growing out of their tongues.
- Big Damn Heroes: Drake and Parry's respective posses.
- Beneath the Earth: The setting.
- Big Bad Friend: The Rebeccas.
- Bizarre Alien Biology: The Styx look human, but actually take the form of whatever their host happens to be at the time. Before they looked like humans, they are known to have at least killed off the dinosaurs, meaning they may have looked like dinosaurs at one point. Every once in a while, they can go through a Phase, where the females suddenly gain insect legs on their backs that can be used to communicate, and get ovipositors growing where their tongues should be. It gets weirder within the Garden of the Second Sun, their natural habitat, where they can grow six legs and three ovipositors. The Armagi are even stranger: they're shapeshifters that can communicate with their detached limbs—and one another—via something about electricity, and can spontaneously grow legs, wings, gills, and what have you to survive in any environment. They're also transparent and Nigh Indestructible.
- Bizarre Alien Reproduction: The Styx appear to reproduce like their hosts for the most part—they can even interbreed with the host species, because, just like Xenomorphs, they use the host's DNA to modify their own appearances to look just like them. But if the conditions are right, the Phase begins, during which the females become parthenogenetic, reproducing without mating, and orally impregnate their hosts with eggs that hatch into lizard-like beings that may, if tended to properly, grow into Armagi, which are shapeshifting transparent creatures that can also somehow reproduce.
- Bizarrchitecture: The Crystal Belt isn't a natural formation.
- Bizarre Sexual Dimorphism: Female Styx can grow giant insect legs and ovipositors during the Phase. Males? Well, they don't. The males just look exactly like their hosts, all the time. Except the Armagi, of course. The all-male Armagi, which Phase-affected female Styx produce, are shape-shifting gelatinous beings somewhere between Starfish Alien and full-blown Eldritch Abomination.
- Body Horror: Anything related to the Phase.
- Boom, Headshot: Several. How Elliott takes out Tom Cox in Closer and how Cal ends the fight with the Limiter in Deeper.
- Brainwashed: One of several purposes of the Dark Light. A surprising amount of people both in the Colony and the outside world have been brainwashed by the Styx.
- Brandishment Bluff: Elliott pulls one of these in Closer.
- Brick Joke: Jiggs is played for drama this way.
- Broken Bird: Chester.
- Call a Smeerp a "Rabbit": Tank-sized dust mites? "Cave cows." Anomalocaris canadensis? "Night crab."
- Carrying the Antidote: And the Idiot Ball, it seems...
- Cave Mouth: The entrance to the Colony rests below an enormous stone skull.
- Changeling Fantasy: Will, though his biological parents actually don't end up being much better at all.
- Cloud Cuckoo Lander: Dr. Burrows is a bit... eccentric, to put it kindly. And then there's Martha.
- Crazy Awesome: Martha varies between this, and just plain crazy.
- Crazy Cat Lady: Mrs. Tantrumi.
- Creepy Child: The Rebeccas.
- Creepy Twins: The Rebeccas.
- Dead Man Switch: Elliott claims to be using such a trigger connected to a backpack full of explosives as leverage to negotiate with the Styx and rescue Will.
- Dead Person Conversation: Will has several conversations with Uncle Tam, though he is clearly a dream/projection from Will's mind rather than a ghost.
- Defector from Decadence: Eddie.
- Delinquents: Speed and his gang.
- Dirty Coward: Downplayed but still present with Sarah during her escape from the Colony. She abandons first one and then both baby sons in order to get herself away clean.
- Disney Death: In Deeper, Caleb is thought dead after his encounter with the Sugar Trap, but gets better.. only to be Killed Off for Real at the end. Also in Deeper, Drake pops up right as rain after an apparent death scene that was pretty traumatic for the protagonists, though only the reader knows he is still alive. Oh, and Jiggs appears to die moments after we first actually see him, but let's be honest, who didn't totally call that he was going to turn up alive and unharmed in the opening chapter of the next book?
- Disney Villain Death: Rebecca One in Spiral.
- Drill Tank: Used by the Coprolites for mining. Drake commandeers one twice, and both times awesomeness ensues.
- Due to the Dead: The "graves" Will makes for his dead relatives in the inner world.
- Dying Like Animals: The Styx want to destroy all Topsoilers, and they always picture it happening like this. [[spoiler: It ends up actually happening when they begin their plot to destroy Topsoil civilization.
- Egopolis: Dr. Burrows has a somewhat alarming tendency to name things after himself.
Dr. Burrows: "The Garden of the Second Sun... I shall call it Roger Burrows Land!"
- Enfante Terrible: The Rebeccas.
- Everything's Better with Dinosaurs: Will and crew encounter some "living fossils", including pterosaurs. Surprisingly, the only genuine dinosaurs they encounter are described as looking like small, cantankerous chickens.
- Evil-Detecting Cat: The Hunters, giant cats kept by Colonists, are experts at sniffing out Styx, and also really don't like them. Funnily enough, the equally giant dogs called Stalkers (normally, it's the dogs that can sniff out evil, whereas cats are often portrayed as accomplice to evil) actually are loyal to the Styx.
- Evolutionary Levels: In Spiral, the Styx are said to be on a higher evolutionary level than humans.
- Exotic Equipment: The Styx females have got one. Giant slimy ovipositors in their mouths to lay eggs down your throat! Sexy, right?
- Eyepatch of Power: Drake's orange lens that allows him to see in the dark. While he doesn't always wear it, he has it on most of the time when he has the boys under his wing, and it is seen to be one of the things that makes him so impressive. Will gets one of his own later, and continues to use it for the rest of the series.
- Face Full of Alien Wing-Wong: How Styx reproduce during the Phase.
- Face-Heel Turn: Eddie. Just when you think that he and Drake are going to overthrow the Styx, he goes and activates the Darklight programming he's put on Drake, leaves him to die in an explosion, and clears out his flat.
- Fair Weather Mentor: When Drake and Elliott find themselves thrown in with Will, Chester and Cal, do they stop to let the boys catch up? Of course not.
- That is, until Drake teaches them how to shoot and fend for themselves. But Elliott is pretty cold to them to begin with, and then again after Drake's "death". Both of them get better later.
- Family-Unfriendly Death: Tom Cox and Sweeney both have their heads blown to pieces by unrelated incidents in the center of the Earth. Also Caleb's death—being shot by over a dozen snipers at once—at the end of Deeper is described in cringe-inducing detail.
- The virus released into the inner world at the end of Spiral.
- Fantastic Racism: The Colonists view the Coprolites as an inferior race suitable only for manual labor. They even give them a demeaning name—a coprolite is fossilized feces.
- Femme Fatale: Every adult female Styx is one, and they know it.
- Foil: Chester and Cal, Will and Elliott, Chester and Elliott, Eddie and Drake, in some perspectives, and even Will and Chester, in a fair few situations. Heck, at some points, it can even seem like everyone to anyone.
- The Fool: Dr. Burrows. While everyone else is fighting for their lives, he wanders in and out of lethal danger without even noticing, being far more interested in trying to decipher the odd hieroglyphic than, say, the numerous predators stalking him or his shortage of food and water.
- It makes sense, though, as he was subject to massive gradual Darklighting.
- Foreign Queasine: The food in the Colony and pretty much anywhere else underground. Eyeless rat is a rare delicacy, and there are far more insect- and fungus-based dishes than Will is comfortable with. For some reason, Anomalocaris doesn't squick him out; he's more concerned about the fact that it's been extinct up top since the Cambrian (read: waaaaay before dinosaurs) and they're just eating it without a second thought.
- From a Single Cell: The Armagi can recover from any injury so long as just one cell survives. Kill It with Fire!
- Fungus Humongous: The fungus growing in the Pore.
- Giant Flyer: While in the Deeps, Dr. Burrows is menaced by an enormous, unseen flying creature that frightens away a cave cow—think "Army tank with legs and bug mandibles." The readers are left to ponder what kind of animal could frighten such a heavily-armored juggernaut.
- Good Is Not Nice: Drake. Eddie. Danforth.
- Government Conspiracy: Done to the Colonists by the Styx; lesser examples occur Topsoil, also courtesy of the Styx.
- The bunker used to travel up and down from the Deeps has hints of this, but isn't as extreme as the usual.
- Gravity Screw: And how! The deeper the protagonists go in the first 3 books, the less gravity there is, and as it turns out there is actually a "zero-gravity belt" between the deepest deeps and the center of the earth. The VERY core actually does have gravity again, in a sort of inside-out crust of a secondary Earth.
- Half-Breed Discrimination: To the extreme when it comes to the (incredibly rare) instance of a child between a Colonist and a Styx. This is forbidden by Styx law, so the Styx parent would be killed and the Colonist parent and child shunned and banished from the Colony.
- Half-Human Hybrid: As mentioned, it's possible for a Styx and a human to have a child together. Elliot is the only known surviving case. She recovers as quickly as a full-blooded Styx, and while she takes longer to enter the Phase, she eventually gets the insect legs too. There's no confirmation of whether or not she develops an ovipositor. But, due to her upbringing, she stays on the side of good even when she gains her bug legs.
- Hands-Off Parenting: Will's mother is glued to the television 24-7, while his father focuses more about archaeology than his family.
- Healing Factor: Styx heal twice as fast as ordinary humans.
- Heavy Worlder: The deeper the protagonists go into the earth, the weaker gravity is, so they can easily carry heavy loads and jump unusually high. They experience the opposite effect when traveling back to the surface after a long time in low gravity: everything is heavy and their movements are slow and labored.
- Heel-Face Revolving Door: Danforth, who ends up killing Chester's parents in an attempt to fool the Styx.
- Hell Hound: The Stalkers.
- Heroic Albino: Will and Cal. Albinism is highly valued in the Colony, as it indicates direct descent from the albino Founders.
- Heroic Bastard: Elliott.
- Heroic Sacrifice: Uncle Tam and eventually Drake.
- Arguably, Dr. Burrows as well.
- Historical In-Joke: The earlier part of the series is loaded with these, especially regarding the Styx's history with the human race.
- Vlad III Tepes carried out his massacres to stop the Styx, actually saving the human race.
- Wellington may have been a Styx, if Eddie is to be believed.
- Adolf Hitler really did look for a way to travel to the center of the Earth. And his soldiers found it, though he himself never got there.
- Hollow World: One is rumored to exist at the very center of the earth, and in the third book, they find it, complete with the descendants of the Germans that Hitler sent there to found his new empire.
- Human Subspecies: The Coprolites seem to be this, though Dr. Burrows suspects they aren't even Homo sapiens at all. In addition, the poorly-understood "bushmen" from the Garden of the Second Sun are humans of some sort, but also talk in the same language as the Styx, but much higher-pitched.
- I'm a Humanitarian: Martha. Chester also commits unintentional cannibalism, thinking the meat he's being fed is from wild birds.
- Insectoid Aliens: The Styx might look human right now, but when they hit the Phase, the females, at least, expose some...definitely non-human parts of their anatomy.
- Ideal Hero: Stealing the limelight from Will, Drake could be viewed as this, although he is slightly hot-headed.
- "I Know You're in There Somewhere" Fight / Beat the Curse Out of Him: Drake uses some of both to break through Chester's mum and dad's brainwashing, making them look through family pictures at knifepoint and eventually resorting to nearly strangling Chester before they recognize him.
- The Illuminati: Drake makes a passing mention to them on one occasion. Either Drake himself was a part of it at one point, or the Styx control it, or both; we never get a clear explanation.
- The Immune: Elliott, after drinking the Dominion vaccine.
- Impact Silhouette: Chester falls into a massive fungus, landing on his back with his arms and legs out, and leaves a Chester-shaped impression. It's fairly deep too, as he has to spend quite some time working himself free from the fungus. Elliott lands on her side so her impression is more of just a blob shape, and we are never shown Will's or Bartleby's. It's described as being far less amusing than it looks in cartoons.
- Innocent Blue Eyes: Will has these at first, but at the end of Terminal, they become red as a result of him possibly becoming a Styx.
- Interspecies Romance: It's possible for a Styx and a human to have viable offspring. But it's heavily frowned upon. Will and Elliot half-count, as Elliot is half-human.
- Ironic Echo Cut: Done several times in Freefall.
Elliott: "We never leave our own behind. [..] He'd do the same for us."
: "Yes, he would. Good old Will."
Will: "Get a move on, or I'll leave you behind!"
- Ironic Nursery Rhyme: You are my sunshine, my only sunshine...
- Jerk Ass: Everybody has their moments due to the stress and tension they're put under throughout the series. Strangely enough, any consistent Jerk Ass in the story mellows out eventually. The only truly consistent example throughout the whole series is, of course, the Styx, especially the Rebecca Twins, who often go out of their way to humiliate Will and make him feel like an idiot before they get down to business and try to kill him.
- Celia Burrows becomes notorious for her pushy, loud, and rude behavior during her time in the mental hospital, mostly out of frustration from being the literal Only Sane Woman. She's insensitive towards the insane patients and monopolizes the television. She rips Sarah up pretty badly, too, when she tries to question her about Will's whereabouts.
- Celia and Roger Burrows' Jerkassery is explained in Spiral as being caused by Darklighting.
- Joker Immunity: Every time you think the Rebecca twins are gone for good...
- Karma Houdini: DANFORTH. Even though he's kinda-sorta a good guy, maybe?
- Knight in Sour Armor: Drake. He is hard and tough, but still has pretty idealistic values.
- Les Collaborateurs: The Styx have agents everywhere. There are even Topsoilers who collaborate with the Colony.
- Let's Get Dangerous: Despite being the biggest of the kids and someone not to be messed with back at school, Chester underground is nearly constantly complaining, easily grossed-out, and generally the least proactive of the group; however, he does have his moments here and there. Most notably the fight between the boys and the limiter where he's pushed far enough to skip over badass and go straight from scared to scary, going crazy for minute and trying to beat the guy to death with his fists.
- He won't forgive the Styx for all those months of imprisonment and daily beatings in a hurry.
- Kill All Humans: Except the ones that are loyal followers of the Styx, of course.
- Kill It with Fire: The ONLY way to deal with Armagi, the shape-shifting supersoldier caste of Styx. They can regenerate From a Single Cell, so don't miss a scrap!
- Let's Split Up, Gang: "No way! Whenever they do that in the movies something terrible happens. We're staying together."
- Lamprey Mouth: In a brief scene in the Eternal City, a fungus with a Lamprey Mouth, which can also swim, is encountered.
- Lost World: Plenty of undiscovered species and living fossils inhabit the Deeps, but the real kicker is the Garden of the Second Sun. It's implied that it's where most of the missing links in evolution existed, and everything from four-winged birds to pterodactyls to quaggas can be found there.
- Mad Love: Martha is obviously barking mad and has a strong but twisted kind of (parental) love for Chester, whom she sees as a substitute for her own dead son.
- Mama Bear: Sarah when she has her mind right. And again, Martha, see above.
- Man-Eating Plant: The Sugar Traps. Yikes. Will has a nightmare about a rock-digesting plant killing his father, but it's Only A Dream.
- Manchurian Agent: Lots of people topsoil, including members of the government, police force, and fruit vendors.
- The Masquerade: The Colony will go to any lengths to keep its existence secret. They have collaborators on the surface, and anyone who stumbles on something they shouldn't or starts asking inconvenient questions gets disappeared. The Styx are actually behind the majority of this business. The Styx are actually doing a double Masquerade—they're keeping the Colony secret from Topsoilers and masquerading as humans in the first place.
- Meaningful Name: Dr. and Will Burrows are passionate about digging and exploration.
- Men Don't Cry: Notably averted in that there are more tears from male characters than from the ladies. Chester cries more than anyone else in the first few books, and in quite an unmanly fashion. We usually see Tears of Fear from Chester, because scary things keep happening to him (being kidnapped, imprisoned, tortured, etc.), and tears of grief from Will, whose companions/relatives keep getting killed. Even Drake weeps as the people of the Rookeries are massacred.
- Mind Probe: The Dark Light.
- Mind Rape: Again, the Dark Light.
- Mole Men: The Coprolites seem to be this. They're friendlier than the normal examples, but not very intelligent.
- Mono Gender Monsters: The Armagi are all male. Not like it matters, as they're shape-shifting killing machines that don't reproduce anyway.
- Multi-Armed and Dangerous: The Styx women during the Phase. If they're in the Garden of the Second Sun, they get even more legs.
- My Species Doth Protest Too Much: Eddie, and several other male Styx if he's to be believed. Elliot seems to be the only female example, and she only half-counts because she's half-human.
- Nigh-Invulnerability: All Styx have shades of this, but the Armagi take it to the extreme.
- No Biochemical Barriers: The Styx are specifically evolved to do this. They assume the DNA and appearance of their current host, becoming so biochemically close to the host species that they can even interbreed.
- No-Holds-Barred Beatdown: The fight between the three boys and the Limiter in Deeper.
- Near Villain Victory: The Styx took down Britain, and very nearly had the rest of the world while they were at it.
- No Name Given: Drake, and arguably Eddie as well, since the name he uses is also an alias.
- The latter does have an excuse, though, given that he is a Styx and therefore no Topsoiler would be able to pronounce his name.
- Not Even Human: In Spiral, the Styx are revealed to be non-human.
- Not Quite Human: The Coprolites appear to be Mole Men, and are renowned for their subservience.
- The Obi-Wan: Uncle Tam.
- Offing The Off Spring: Sarah's plan for Will, believing that he betrayed Tam to the Styx.
- Orifice Invasion: How the Styx reproduce during the Phase.
- Our Angels Are Different: Dr. Burrows suggests that Brights, which are basically giant flesh-eating flying insect-like creatures with lights on their heads like anglerfish, may have inspired depictions of angels when they emerged to the surface ages ago. They actually turn out to be fiercely protective of whatever creature they imprint on, so when Martha manages to hatch a brood of them from an adult she captures single-handedly, they work as her "guardian angels."
- Our Monsters Are Weird: Ever so weird.
- There are cave cows, which are sort of like tank-sized dust mites.
- The Eternal City is inhabited by, among other things, swimming fungi with lamprey-like mouths.
- Brights are bioluminescent insect...things...that can move faster than the eye can see.
- Spider monkeys, Not to Be Confused with the primate of the same name, are arachnid...things...that use echolocation.
- Anomalocaris canadensis is still alive and kicking in the Deeps—bonus points for using a Real Life weird monster!
- The bushmen. They're suspected to be a Human Subspecies, but that's not certain, because they speak Styx.
- The Styx, in general. The more we learn about them, the more bizarre they seem to get.
- And the Armagi, the final part of the Phase, are even weirder than the Styx that give rise to them.
- Parental Abandonment: Sarah Jerome ditches both her sons when escaping the Colony. Also the Burrows parents in their own way. Both are so caught up in their on obsessions (Celia's TV and Roger's archeological work) that they don't take care of their children at all. If anyone is the parent in the Burrows house, it's Rebecca, who does all the family's cooking, housekeeping, and bill-paying. Later they both literally abandon their family as well, Roger disappearing and going off on his own underground adventure and Celia going to live at a sanitarium and leaving her children with her equally-irresponsible sister.
- Phlebotinum Killed the Dinosaurs: Styx killed the dinosaurs during a Phase.
- The Plague: Dominion, a strain of influenza engineered by the Styx to eradicate life on the surface.
- Plant Person: The natives of the Garden of the Second Sun. Though they're actually a Human Subspecies, and look human underneath all their leaf-like skin.
- Planet Spaceship: Earth itself turns out to be one at the conclusion of Terminal. It's been out of service for billions of years, ever since the Styx lost control of it and it settled into orbit around the Sun, but it gets reactivated at the end of Terminal and starts heading home.
- It's vaguely hinted that the moon may be a sort of companion, as the tower in the center of the Earth has live feeds of the Earth's surface being sent to it right now from a very large, but undetected, object in orbit. Unless it's invisible, the moon is the only thing this object could be.
- Power Crystals: In Freefall, the Crystal Belt is discovered, containing dozens of crystals the size of mountains crashing against one another to produce flashes of triboluminescence. In Terminal, it turns out that these aren't a natural feature; they're actually laid out in a uniform fashion and are powered by mysterious technology and are some kind of mechanism to propel Earth through space.
- Power Glows: The mysterious, seemingly magical technology that Elliot can control due to her Styx heritage glows brightly whenever she touches it.
- Precursors: It turns out the Styx are these. After an unknown event billions of years ago they simply forgot who they are. They were traveling on a Planet Spaceship when a catastrophe occurred, they lost control, and Earth fell into orbit within the Sun's habitable zone and life colonized its outer hull, giving rise over billions of years to the world we know today.
- Properly Paranoid: Sarah when topsoil. Drake and Elliot in the Deeps. Chester thinks of himself this way almost word-for-word in Closer. Martha in general.
- Psychic Static: "I pray that I might not let those about me spoil my peace of mind."
- Rape as Backstory: Implied in the brief mention of Elliott's history.
- Redemption Equals Death: Sarah
- Religion of Evil: The Book Of Catastrophes.
- Replacement Goldfish: Martha tries to adopt Chester as a replacement for her dead son.
- Retired Badass: Parry, as well as the rest of the Old Guard.
- Scenery Porn: There's plenty of amazing geography in the Deeps. Later, Will and Dr Burrows are freefalling to the center of the earth, and the subsequent travel through the gravity belt is quite dramatically described. Also, the Garden of the Second Sun is beautiful. Until the protagonists unintentionally destroy its biosphere. Twice.
- Seldom Seen Species: Anomalocaris canadensis and devil's toenail molluscs make a brief appearance in Deeper...as food. Also, Palaeomastodon appears briefly in Closer, as do a herd of quagga.
- Servant Race: The Coprolites to the Colonists and Styx alike. Also, the bushmen to the Styx when the Styx inhabited the Garden of the Second Sun, though they abandoned that world a long time ago; and if Elliot's suddenly-acquired race memory is accurate in Terminal, there was another Servant Race that rebelled against the Styx billions of years in the past that caused the Planet Spaceship to stop traveling and settle into orbit around the Sun, gradually turning into Earth as life colonized its outer hull and made it habitable. She says it was the humans that rebelled, but this would have happened billions of years before humans even evolved. Her mistake is excusable because she's probably never had an adequate paleontology lesson in her life.
- Shown Their Work: The authors really show their work in the earlier novels, as every single Historical In-Joke and historical reference fits perfectly into real-world history.
- Single-Minded Twins: The Rebeccas.
- Only at first. Through the course of the books, their personalities diverge quite a bit. Rebecca Two is far milder and much more rational. She rarely suggests the use of violence and acts quite kindly to several character. Her sister, on the other hand, is very dominating and quite ruthless.
- Sinister Scythe: The weapon of choice for the Styx.
- Sour Supporter: Elliott and Chester are both this for Will in Deeper and Freefall, but become less "sour" and more "supporter" as the story goes on.
- Spider People: For unknown reasons, if a Styx female affected by the Phase enters the Garden of the Second Sun, she will sprout an additional two sets of insect legs. In addition, during the Phase, females who are impregnating males swell up into bloated versions of their former selves. Combining the two makes them resemble giant spiders, which Will and his companions never miss a chance to mention.
- Spirit Advisor: Uncle Tam to Will. Implied that Martha's dead son may be something of this to her...except she's actually crazy.
- Starfish Language: The Styx speak in what appears to be a buzzing, barking language that can't be deciphered or understood, and sometimes borders on Black Speech. During the Phase, the females can use their insect limbs to make a humming sound to communicate over long distances and command hordes of Armagi.
- Statuesque Stunner: Adult female Styx are described as being very tall and extremely attractive, in a cold, detached sort of way.
- Straight Man: Eddie, somewhat.
- Straw Nihilist: Elliot seems to think this way, though it is downplayed and not used to make philosophical arguments. She is more cynical than Drake despite being much younger, and her spiel in Deeper about how everyone is wormfood certainly fits this trope.
- Stuff Blowing Up: Drake and Elliott both carry a lot of explosives. Whenever they're faced with a problem, the first solution is to blow it up. In a whimsical moment Will even imagines a superhero alter ego for Elliot, the Exploding Girl, who has nitroglycerin for blood.
- Stupid Neutral: The Coprolites appear to possess no survival instinct, and will passively let the Styx line them up and execute them without resistance, though this may be justified by their having been enslaved for generations and accepting this as the normal course of life.
- Stupid Scientist: Being off on his own adventure for the first half of the series and an Absent-Minded Professor to being with, Dr. Burrows never gets to see the Styx's brutality or anything about the Dominion plot. So he thinks Will and Drake are just being paranoid to run from them and stubbornly refuses to accept that the Styx are dangerous or that the Dominion could even happen right up until his death at the hands of Rebecca.
- Sufficiently Advanced Aliens: The Styx turn out to be these. And they built Earth.
- Supersoldier: Sweeney and quite possibly Jiggs.
- Talking to the Dead: Will does this a couple of times, notably in Deeper after he fails to keep his promise to protect Cal.
- The Ghost: Jiggs in Spiral. Until one paragraph at the very end.
- To absent, and very brave, friends.
- Trigger Phrase: Used by the Styx. Sensibly, the phrases are in the Styx language, so they can't be triggered accidentally.
- The End of the World as We Know It: The Styx attempt to do this, twice. And then it's actually done by Elliot, of all people, by reactivating the Earth's engines and making it leave orbit and head home. The result is that the entire Earth's surface becomes a frozen wasteland, killing off all life up there; it's implied that the majority of people actually survive by moving into the Colony.
- They Look Like Us Now: The Styx look like their hosts enough to pass for the same species. They didn't look like humans until around twenty thousand years ago; it's implied that they took Cro-Magnons as their hosts and killed off the competing Neanderthals in the process.
- Twin Switch: Done regularly by the Rebeccas.
- The Unmasqued World: The Book of Catastrophes foretells this, calling it the Discovery and warning that the Topsoilers will destroy the Colony unless the Colonists destroy them first.
- Too Dumb to Live: Downplayed by Dr. Burrows. The Styx were going to kill them anyway, but he outright called their bluff and volunteered to be the victim, despite all the ruthless and vicious things happening around him. It wasn't the first example either.
- "Well Done, Son!" Guy: Downplayed. Will is revealed to be something of this in Deeper when Rebecca derides him for spending so much time digging and helping Dr. Burrows, "digging for daddy's love".
- What Happened to the Mouse?: The character Jiggs is mentioned several times throughout the book by Drake and Parry. For several hundred pages not one mention of him is made, until he suddenly appears in the Garden of the Second Sun, kills several Limiters, distracts the Rebeccas, saves Will, and tumbles into the inner space of the Earth's core, and is presumably killed. He doesn't die.
- Wild Card: Eddie.
"He's not on your side anymore!"
"Well, whose blooming side is he on then?"
- Ultraterrestrials: The Styx.
- The Unpronounceable: The language of the Styx can't be pronounced by humans, or even represented by letters and words.
- Yandere: Martha.
- Yank the Dog's Chain: Poor Chester gets his chain yanked twice. First is Will's disastrous attempt to rescue him from the hold in the first book where everyone gets away except Chester. And then he spends months underground wanting only to go home to his family on the surface, but when he's finally reunited with his parents, they've been brainwashed and don't recognize him as their son. Fortunately Drake is able to fix them.
- Only for them to be killed the very next book. By a double agent who later turns out to be a triple agent. Understandably, he doesn't take it well. Then, he is killed in the next book by Martha.
- You Cannot Thwart Stage One: The Dominion virus still ends up in Styx hands by the end of Closer despite several books being spent trying to get rid of it entirely. However, Will and Eliot do at least manage to get the cure to the surface. Then in Spiral there is a double subversion; the first phase is averted without any difficulty, meaning stage one is thwarted. However, the backup Phase goes ahead on the surface, effectively making things worse than if stage one hadn't been thwarted.
- You Have Outlived Your Usefulness: Standard Styx procedure towards anyone who helps them.
- You Shall Not Pass: Uncle Tam's death in Tunnels.
- You Wouldn't Shoot Me: Roger doesn't say this exactly, but his sarcastic "if you want to murder someone, you can start with me" counts. As it turns out the person he's taunting really would shoot him. A lot.