Follow TV Tropes


Literature / Gideon the Ninth

Go To
The most fun you'll ever have with a skeleton.

IN THE MYRIADIC YEAR OF OUR LORD—the ten thousandth year of the King Undying, the kindly Prince of Death!—Gideon Nav packed her sword, her shoes, and her dirty magazines and she escaped from the House of the Ninth.

Gideon the Ninth is the first book in The Locked Tomb Series by Tamsyn Muir. It was released on September 10th, 2019.

Gideon Nav is a foundling who was taken in by the ancient House of the Ninth, last of the Emperor's great Houses, on the day she was born. She and Harrowhark Nonagesimus, the heir of the house, are the only children left on a planet otherwise populated by animated skeletons and dying cultists. Gideon has been trying to escape for nineteen-odd years, despite Harrow blocking her at every turn.

After her latest failure, a new opportunity arises. Harrow has been invited to the First House to attempt to become a Lyctor, an immortal saint of the Emperor. Tradition and propriety require her to have a personal cavalier, a sword-fighter sworn to her service. Unfortunately, there are no appropriate candidates left in the House of the Locked Tomb, so Harrow convinces Gideon to take the job instead.

The First House, however, isn't quite what either of them expected. Instead of being instructed in the most ancient secrets of necromancy, the heirs of the Houses are set loose in a haunted tower with no guidance or assistance. They are expected to somehow discover the secrets of Lyctorhood by searching through ten thousand-year-old experiments left behind by the original Lyctors. Harrow abandons Gideon immediately, leaving her to wander around aimlessly, listening in on the heirs of the other Houses, from worlds populated by more than senior citizens and bone constructs. She spends most of her time bored out of her skull.

And then people start dying.

This novel provides examples of:

  • Abandoned Laboratory: The locked lower levels of Canaan House contain a series of creepy, abandoned labs with the remnants of necromantic experiments. They're also supposed to be haunted and, as Gideon paraphrases, "chocka full of ghosts."
  • Academy of Adventure: Briefly discussed and parodied by Gideon. The heirs were expecting Canaan House to be this, and are disappointed to find it is very decidedly not a school of any kind. It's eventually subverted, as Canaan House was meant to teach the heirs various advanced necromantic techniques with the ultimate goal of teaching the method to achieve Lycthorhood.
  • Action Bomb: Palamedes blows himself up by detonating his thanergy reserves in an attempt to kill Cytherea.
  • Aerith and Bob: Several characters in the book have names that would be considered perfectly normal in real life—Judith, Marta, Isaac, Abigail, Camilla, and Silas—and a few more that would be pretty uncommon but not unheard of, like Jeannemary, Magnus, and Gideon herself (though hers is a Gender-Blender Name that you'd be way more likely to see in a man). You're probably pretty unlikely to encounter someone with the same name as the rest of the characters in the book, such as Harrowhark, Protesilaus, or Colum.
  • Alas, Poor Villain: Naberius the Third is one of the most unpleasant visitors to Canaan House, and pretty much nobody likes him except maybe the Third twins, occasionally. But after Ianthe callously reveals to the Sixth, the Eighth, and the Ninth how Lyctors are created and that she murdered him to achieve this, they're horrified, and the Eighth immediately challenges her to a fight to attempt to bring her to justice.
  • All Love Is Unrequited: Camilla Hect is implied to be in love with her necromancer Palamedes Sextus, who only has eyes for Dulcinea Septimus, who is fixated on Gideon Nav, who definitely has the hots for her, too, but gradually develops deeper, truer feelings for Harrow, who's been in love with the body in the Locked Tomb since she was 10 years old. When Gideon learns about Palamedes's history with Dulcinea, she lies face down on the floor and sobs at the messiness of it all. Camilla is later implied to be asexual and have some sort of three-way understanding with Palamedes and the real Dulcinea.
  • Anyone Can Die: When all the dust settles at Canaan House, out of all the characters, only Harrow and Ianthe are found alive by the Empire, with Coronabeth, Judith, Camilla, and Gideon's corpse having all vanished.
  • Anywhere but Their Lips: Gideon carefully kisses Harrow on the top of her nose after they clear the air.
  • Arc Words:
    • Gideon the Ninth, as the introduction to the series, frequently references a phrase to describe the bond between necromancers and cavaliers: "One flesh, one end." It's both a ritual phrase that is invoked in ceremonies binding a cavalier to a necromancer, and shorthand to describe their shared actions and fates. Having been created by the First cavaliers, it also has a much more literal meaning, given the process by which Lyctorhood is achieved. Gideon rephrases it another way before she pulls her Heroic Sacrifice as meaning "There is no me without you."
    • Along the same lines, as people start dying at Canaan House, several characters use a variation of the phrase "No necromancer/cavalier should have to see their cavalier/necromancer die".
  • An Arm and a Leg: Ianthe's right arm is chopped off in the battle with Cytherea.
  • As the Good Book Says...: Inexplicably, Gideon of all people quotes Ruth 1:17 to Harrow in the penultimate chapter of Gideon the Ninth.
  • Asshole Victim: Naberius Tern, the Smug Snake cavalier of the Third House who acts condescending towards all the other houses, is betrayed and killed by his necromancer, Ianthe, late in the book so she can ascend to Lyctorhood. While the other surviving houses are disgusted by her complete lack of remorse and the ease with which she was willing to kill him, none of them mourn his loss on a personal level, and the reader is unlikely to, either.
  • Attack Its Weak Point: Harrow is able to tell the weak points of bone constructs, where hitting them at all those points in the right order will unravel the theorem that had allowed the construct to behave as if alive in the first place. However, as she isn't good at sword fighting she sometimes does a Mind Meld with Gideon to tell her where to hit them.
  • Awful Truth: As the heirs work through the mysteries of Canaan House, it becomes increasingly obvious that Lyctorhood is not entirely what the Empire's worship of God's Necrosaints led them to believe. Ianthe, as the first to ascend, lays it out bluntly to the remaining heirs:
    Ianthe: "Ten thousand years ago, there were sixteen acolytes of the King Undying, and then there were eight. Who were the cavaliers to the Lyctors faithful? Where did they go?"
  • Aw, Look! They Really Do Love Each Other: All necro and cav relationships have a healthy degree of playful banter and fighting, except for the Eighth and Ninth, but even they end up showing that they care about each other.
    • Harrow and Gideon share a... complicated relationship. Despite their frequent assertions that they'd love to see the other die a painful death, whenever one of them is actually in real danger of dying, the other freaks out and becomes protective.
    • Likewise, Silas is an even bigger jerk than Harrow, and treats Colum like a servant despite him being at least a decade older, but when Colum is in real trouble he genuinely loses his shit over it (especially because it's at least half his fault).
    • Magnus is pretty much the Team Dad to the young teenagers Isaac and Jeannemary, who accordingly see him like an Amazingly Embarrassing Parent and act very embarrassed by his dad jokes and proud parent-like boasting about them (with the added political complication that them being openly loyal/beholden to Magnus and Abigail would essentially make the Fourth House subservient to the Fifth). But when he and Abigail, their Team Mom, are murdered, both teens are absolutely devastated, and their number-one priority from then on becomes avenging their deaths.
  • Bait-and-Switch: Right before the climax, Gideon catches up with Palamedes outside of Dulcinea's quarters, having just found out about his past relationship with her from Camilla and wanting to make things right with him. As she opens her mouth to apologize, though, he uses necromancy to pin her in place and keep her silent, while looking at her "cold and dispassionate, unlike himself". It at first looks like he's either acting out of jealousy to keep her away from Dulcinea or, even worse, planning to kill Dulcinea himself and stopping her from interfering. In fact, he's doing this to protect her; by now, Palamedes has realized that "Dulcinea" is really an imposter and is preparing to confront her and then try to kill her, and is keeping Gideon safe by preventing her from stepping in or revealing her presence and ensuring she's far enough away from his Heroic Suicide that he won't injure her.
  • Bear Hug: Gideon gives Harrow one that lifts her off the ground. This surprises and flusters them both.
  • Because You Were Nice to Me: The reason that Gideon is so upset by Magnus the Fifth's death. He was practically a stranger, but he is the first person in her life to treat her kindly without any sort of ulterior motive.
  • Belligerent Sexual Tension: Harrow and Gideon, although their animosity is more rooted in real resentment and pain than in typical examples.
  • Big Damn Heroes:
    • Right after Camilla has defeated Marta as part of the Second's challenge to duel the Sixth, the skilled duelist Naberius the Third also challenges the Sixth for their keys while Camilla is injured and weakened. Unexpectedly (from the other Houses' perspective, at least), Gideon decides to step in to duel in her place—with Harrow backing her up—and then Jeannemary the Fourth jumps in to declare that he'll have to fight her afterwards as well. This is enough to get Naberius to rescind the challenge and back off.
    • Ianthe, of all people, pulls this off twice:
      • Silas siphons Colum in an attempt to fight her, but this causes Colum's body to become possessed by angry ghosts. Gideon attempts to fight off Colum's ghost-possessed body, but just as they get the better of her, Ianthe intervenes and forces the ghosts out of Colum, which leaves behind a lifeless corpse.
      • In the final battle, Cytherea has literally pinned down Camilla and is about to run her through with her rapier while Gideon is injured and too far away to help, and Harrow is unconscious. Cytherea is then Impaled with Extreme Prejudice In the Back Just in Time by Ianthe; of course, this isn't enough to kill her, but it does give Gideon, Harrow, and Camilla a chance to get farther away and regroup while the two Lyctors battle it out.
    • Camilla returns the favor for the above by throwing her dagger at Cytherea to impale her weak point, drawing her aggro away from maiming Ianthe any further after already cutting off her right arm.
  • Big Guy, Little Guy: The Eighth House pair of massive Colum and his creepy younger uncle Silas.
  • Blood from Every Orifice: A common side effect of necromantic exertion is sweating blood from the pores; more powerful displays of necromancy cause even more bleeding and burst capillaries, escalating to this trope. Harrow, being both powerful and prone to overexerting herself, ends up covered in her own blood at several points as a result of pushing herself too hard. Siphoning can also cause this, as Gideon discovers when Harrow is draining her in the Avulsion trial.
  • Bodyguard Crush: Cavs and their necros share a very intimate and close relationship. For those to whom it's not a familial relationship, there's often some romantic tones to the bond, which is lifelong and not dissimilar to a marriage; in the case of the Fifth, they're literally married.
    • Especially implied to be the case for Camilla's feelings toward Palamedes, whom she's sworn to protect and look after.
    • It's also teased a lot between Gideon and Harrow; Gideon's feelings for Harrow grow in tandem with her commitment to her duty as cavalier, and as they grow closer Gideon's narration is shocked to find anything attractive about her lifelong tormentor, but she starts to find things regardless.
  • Book Ends: The final fight of Gideon the Ninth has a number of symmetries with the earlier parts of the story.
    • When she spars against the other cavaliers in the early days at Canaan House, Gideon defeats Magnus in three moves, and is caught off guard by Naberius' trident knife. She also gets past Cytherea's guard within three moves and makes a killing blow, only to be foiled by her Healing Factor, and on her second attempt, Cytherea catches her two hander like Naberius' trident knife.
    • When Gideon's narration recounts her mysterious origins, it begins with "Nav was a Niner name." The exact same phrase is repeated near the very end of the book as Gideon lets go of her hatred of the Ninth right before killing herself to save Harrow and Camilla.
  • Break-Up/Make-Up Scenario: Just as Gideon and Harrow seem to have reached a more comfortable place in their relationship, they have an explosive falling-out after the deaths of the Fourth. They reconcile for good a few chapters later, shortly before the climactic confrontation of the book.
  • Building of Adventure: Nearly all of Gideon the Ninth takes place inside the mysterious, abandoned Canaan House.
  • Characters Dropping Like Flies:
    • The deaths start slowly, with Act 2 ending in the deaths of Magnus and Abigail the Fifth, and in Act 3, Protesilaus the Seventh goes missing, shortly followed by the deaths of Isaac and Jeannemary the Fourth at the end.
    • Then come Acts 4 and 5 and the body count skyrockets, starting with the reveal that Protesilaus was Dead All Along, and now his corpse has been destroyed, then Gideon's discovery that Ortus and Glaurica were Killed Offscreen when they stole her shuttle, and continuing with, in fairly rapid succession, the confirmed deaths of Marta the Second, Teacher and the other priests, Naberius the Third, Silas and Colum the Eighth, Dulcinea the Seventh (or more accurately, the reveal that she was also Dead All Along), Palamedes the Sixth, Gideon the Ninth herself, and Cytherea the First.
    • By the end, only two characters (Harrow the Ninth and Ianthe the Third) are confirmed to still be alive, with three more characters' statuses unknown (Judith the Second, Coronabeth the Third, and Camilla the Sixth).
  • Chekhov's Gun: When recounting her backstory, Gideon's narration briefly mentions a catastrophe that killed most of the children of the Ninth, but doesn't go into any detail. The true details of this event are discussed much much later, the darkest secret of the Ninth that explains Gideon's upbringing and the twisted relationship between her and Harrow.
  • Chekhov's Skill: Psychometry, the Sixth House's knack for reading and tracing the echoes of life that death leaves on objects. It's how Palamedes realizes "Dulcinea" is behind the murders, when his hand brushes against the message on the wall she left in the last locked Lyctor room.
  • Childless Dystopia: Childless because of a vent flu 18 years ago wiped out almost every child of the Ninth, making Gideon and Harrow literally the only members of their house's entire generation. Dystopia because of the monastery's general state of decay and disrepair, then underlined with the fact that everyone on the planet is getting old and gray with no one to replace them, and that the "flu" was actually nerve gas that Harrow's family used to kill 200 children to ensure Harrow's conception as a necromancer.
  • Closed Circle: Caanan House was deliberately cut off from the rest of the universe so that the necromancers can focus on achieving Lyctorhood. This becomes a problem when people start dying, as no one can escape or call for help.
  • Cooldown Hug: Gideon gives a crushing one to Harrow, when she has a breakdown after laying bare her soul and demanding Gideon to strike her down for everything she'd done to her.
  • Cool Sword: Mentioned but ultimately subverted. While some of the affluent Houses have gorgeous weapons, the more dangerous cavaliers have plain or even tattered looking weapons, and Gideon's beloved two hander is noted as being plain and perfect for it.
  • Covers Always Lie: Reviews and blurbs about the book always bring up Gideon's dirty magazines. They're mentioned only a scant few times, never shown, and aren't remotely plot relevant.
  • Creepy Basement: The locked lower levels of Canaan House where the Lyctor challenges are located.
  • Damn You, Muscle Memory!: Gideon has been trained by Aiglamene since she was a young child to fight with a two-handed longsword, and she excels at it. But when she's recruited to be Harrow's cavalier, she has to retrain to use a one-handed rapier, as is the custom for cavaliers, and uses iron knuckles on her off hand. Gideon frequently has to fight her well-honed instincts for using her longsword so she can properly hold, parry with, and dodge with the rapier, to her frequent frustration.
  • Dead All Along:
    • Both of the Seventh House members, who were actually murdered by Cytherea the First before ever arriving at Canaan House. Cytherea (formerly a member of the Seventh House herself) poses as Dulcinea (the necro) and puppets the corpse of Protesilaus (the cav) in a similar way that Harrow does with her own parents' corpses.
    • Teacher and the other two priests, who are corpses being controlled by revenants.
  • Dead Person Conversation: The penultimate chapter before the Epilogue has Gideon's spirit comforting, guiding, and teasing Harrow after the former's Heroic Suicide before she fades away completely.
  • Dead Person Impersonation: Neither the characters nor the reader get to meet the real Dulcinea Septimus during the events of the book; the "Dulcinea" we see is actually Cytherea the First, who pulled a Kill and Replace on her before her first appearance in the book. It helps that, thanks to Cytherea originally being from the Seventh House herself, she strongly resembles Dulcinea, and since no one at Canaan House has ever met the latter in person, she's able to pass herself off as her.
  • A Death in the Limelight: Several times over, in fact!
    • In Chapter 15, the Fifth host a dinner party for their anniversary, which is the first time Abigail, the Necromancer of the Fifth, gets a chance to speak, and alludes to her and Magnus being unable to conceive, a manuscript about Lyctoral history that she's been working on, and her necromantic specialty. She and Magnus are the first to be killed by the end of the next chapter.
    • In Chapter 25, we finally spend more time with Jeannemary and Isaac, and get to learn more about their backstory. They're both dead by the end of the chapter.
    • Chapter 28 has Gideon actually sit down and talk to the Eighth for the first time, revealing a lot about their House and the relationship between Colum and Silas. A few chapters later, Chapter 34 is the first time the Eighth show their fighting skills, and end up dead.
  • Demonic Possession: Teacher warns something like this is bound to happen if you leave a soulless body in an insanely Haunted Castle for any amount of time. Silas does not listen, and both he and Colum pay for it.
  • Designated Girl Fight: Roundly subverted; the most serious duels and fights between fellow humans are all between women. Even the lightest one, a quick skirmish between Camilla and Gideon before Palamedes breaks it up, leaves them with a healthy respect for each other.
    • The most violent and intense duel between cavaliers in the book is the only one between two women, Marta and Camilla, which ends with the former bleeding and with a dislocated arm while the latter also has a deep cut on her arm.
    • Most notably, all of the men at Canaan House have been killed by the time we reach the extremely bloody, gorey Final Battle, which thus only takes place between women.
  • The Dog Was the Mastermind: With a twist. As more and more of the heirs and cavaliers at Canaan House turn up dead, the surviving cast attempts to find and stop the killer. Said murderer seemingly turns out to be Dulcinea Septimus, considered probably the least likely suspect because she's so ill that she spends most of the book unable to move around on her own. But then it's revealed that the woman they all knew as "Dulcinea the Seventh" has actually been an imposter the whole time, Cytherea the First, a Lyctor who Killed and Replaced Dulcinea and used her necromancy to commit the murders (or at least some of them) remotely while remaining bedridden.
  • Downer Ending: Gideon the Ninth ends in a very sad place as a set up for the next book: Gideon, Palamedes, and all of the supporting characters are dead or missing, with only Ianthe and Harrow found alive by the First. Harrow is utterly devastated by Gideon's death and near suicidal, which prompts the drastic decision she makes in Harrow the Ninth that shapes the entire book.
  • Dramatic Irony: In the bonus materials included at the end of the paperback version, Judith's Cohort intelligence files, which were created before everyone arrived at Canaan House, speculate that Princess Ianthe the Third isn't actually a necromancer (or is at least a very poor one) and is using her older twin sister, Crown Princess Coronabeth, as a cover, especially since Judith observes that Ianthe only seems to perform necromancy when Corona is present. As it turns out, the exact opposite is true: Ianthe is, in fact, a very capable necromancer, and Corona is the one who was born without necromantic powers and hides behind her sister's skills.
  • The Dulcinea Effect: A quite literal example, considering that two different characters develop this for Dulcinea Septimus:
    • When Dulcinea first emerges from her shuttle, she collapses due to her illness, and Gideon instinctively rushes over to catch and help her. She quickly becomes infatuated with her afterwards.
    • Palamedes fell in love with Dulcinea when he became her pen pal at eight years old (while she was 15) and even began learning medical necromancy solely for the purpose of being able to take care of her and help cure her disease. This went on for 12 years, despite him never even meeting her in person until the events of this book.
  • Dwindling Party: The body count begins with Magnus and Abigail, and only grows from there. By the end of the first book only two of the nineteen named characters at Canaan House are found alive, with three others last seen alive but missing, and one vanished corpse.
  • Dying Declaration of Love: Gideon briefly tries to pretend this was the case with Palamedes, telling Camilla his last words were, "Tell Camilla I love her." Camilla does not buy this for a second, and Gideon immediately backtracks.
  • Eating the Eye Candy: Gideon indulges in this a lot, usually when Coronabeth is flouncing around her in skimpy nightgowns or a wet swimsuit, though her attraction to Dulcinea is more chaste and often fixated on her eyes and hair. Harrow isn't immune to Coronabeth either.
  • Eldritch Abomination: Canaan House is ridiculously haunted, and there are constant suggestions that something is down in the labs. When a bone golem starts killing people in impossible ways, it's almost a relief. Canaan House itself ends up not being the real danger, with Cytherea and her construct behind the murders of the Fourth, Fifth, and Seventh. But Silas finds out first-hand that the vengeful ghosts of the First are not just an ominous warning when a number of them possess Colum's empty body and stab the necromancer through the throat.
  • Elective Mute: Vows of silence are common for religious penitents of the Ninth. Harrow, who has been puppeteering her parents' corpses for seven years, claims they'd both taken the vow. Most of the other Houses also assume Gideon is under a vow of silence for the first half of the book, as Harrow ordered her not to talk to anyone for fear of her saying something stupid.
  • Even Evil Has Standards: Ianthe Tridentarius is one of the least likable members of the cast at Canaan House, being a Smug Snake who forbids Naberius from intervening at Corona's behest in Judith's challenge to the Sixth largely for her own amusement, and then shows her true colors when she murders Naberius with no remorse to become a Lyctor, all while condescendingly bragging to the others that she figured out the secrets of Lyctorhood before they did. However, she's notably willing to side with the protagonists against greater, far more evil threats:
    • She's actually pretty helpful to other members of the group several times throughout the book. After Abigail and Magnus die, she joins the other necros in giving her all to try to call back and communicate with their spirits in an attempt to save them. She also pulls Big Damn Heroes moments twice to save Gideon from the possessed Colum and Camilla from Cytherea.
    • Furthermore, though she kills Naberius because it's necessary to achieve Lyctorhood and is completely unapologetic about it, she doesn't seem interested in killing any of the other guests (her potential rivals) at Canaan House. Naberius is her only kill in the book, she's insistent about not being responsible for any of the other deaths when accused of it, and when Silas prepares to fight her to punish her actions, she entreats the Ninth and Sixth to stop him (which they attempt to do, to no avail) because she doesn't want to spill any more blood. She also, as mentioned above, saves a cavalier from another House at two different times.
  • Everyone Has Standards: Though Colum the Eighth despises the man that his much younger uncle Silas has become, he nonetheless loyally follows his orders most of the time. However, Silas later invites Gideon to visit him for information (which he does give her) with the intention of challenging her for her keys afterwards—knowing that she won't be able to fight back against Colum because she was forced to hand over her weapons at the door and thus will have to forfeit and give him the keys to leave safely—while completely unashamed of it, his reasoning being pretty much "The Ninth are all evil liars anyway, so there's no reason to feel bad about double-crossing them." Colum, who didn't know what Silas was planning and earlier promised Gideon when confiscating her weapons that there would be no violence, is utterly horrified and disgusted that he would pull such a dirty trick and ask him to compromise his honor like this; he finally tells his uncle off, refuses to comply with the challenge, and returns Gideon's possessions and lets her leave unharmed.
  • Exact Words:
    • The first step in achieving Lyctorhood is to understand precisely what Teacher means by "You must never enter a locked room without permission." He is in fact encouraging them to ask his permission, in which case he'll hand them the key.
    • Subverted with Cytherea. This character insists they never actually lied (going strictly by a technical interpretation, they in fact never do tell a straight lie), but Palamedes dismisses this contemptuously.
  • Extremely Short Timespan: Downplayed. Act 1 has a Time Skip of three months, and there are several boring weeks at Canaan House brushed aside in the beginning of Act 2, but the middle of Chapter 12 until the end of the book takes place in under a week, getting increasingly compressed over time, such that half of the book (from Chapter 22 onwards) takes place within 72 hours.
  • The Faceless: Present but subverted and even lampshaded due to it applying to the primary protagonists. With the combination of thick hooded robes, heavy face paint, and coverings over the eyes, the Ninth House falls right into this trope from the perspective of outsiders. Gideon even finds some benefit to concealing her emotions, for all that she otherwise loudly complains about it being a pain. However, her narration sees right through all of it, because she has spent her whole life around it, especially for Harrow.
    [referring to Harrow being flustered by Palamedes trusting her]
    To an outsider, it would have just been a blank Ninth House mask twinging from darque mystery to cryptique mystery, giving nothing away, but to Gideon it was like watching fireworks go off.
  • Fantastic Racism: The Eighth really hate the Ninth, to the point that Silas won't even tolerate eating breakfast in the same room as Gideon. She later discovers that they have somewhat understandable reasons for not trusting the Ninth House, but Silas takes it way too far, in the vein of Misplaced Retribution.
  • Fantasy Gun Control: Aside for an unclear reference by Aiglamene about using "powder" as an offhand weapon, there is exactly one gun in this book, a 10,000-year-old but perfectly preserved carbine rifle, Gideon’s amazed reaction to which implies that the Empire hasn’t fielded firearms in a very, very long time.
  • Final Speech: Both Palamedes and Gideon get one, as the two characters who commit Heroic Suicide rather than being killed suddenly. Palamedes' speech to Cytherea doubles as a Shut Up, Hannibal! speech, while Gideon gives one right before her Heroic Suicide.
  • Foil: Most of the other cavalier and necromancer duos at Canaan House parallel Gideon and Harrow, and the relationship between them, in some fashion, though it's strongest with the Sixth, Third, and Eighth.
  • Foreshadowing: The series features a lot of extensively foreshadowed events, so much so that they're listed separately here.
  • Four-Temperament Ensemble: Broadly speaking, of the principal cast that ends up working together, Gideon is sanguine, Harrow is choleric, Palamedes is melancholic, and Camilla is phlegmatic.
  • Furnace Body Disposal: Soon after two participants in the Lyctor trials are murdered, the survivors find more human cremains in an incinerator. Being Necromancers, they can easily tell that the ashes are of two people who died before the trials began—apparently impossibly, since the participants are completely isolated. They're eventually revealed to have been the corpses of Protesilaus and the real Dulcinea, who were Dead All Along, as their killer, Cytherea (the fake Dulcinea), needed to dispose of the bodies.
  • Gender-Equal Ensemble: Almost perfectly with the characters at Canaan House:
    • Of the eight cavaliers in attendance, four are women (Gideon the Ninth, Camilla the Sixth, Jeannemary the Fourth, and Marta the Second), and four are men (Naberius the Third, Magnus the Fifth, Protesilaus the Seventh, and Colum the Eighth).
    • The heirs/necromancers are certainly more skewed towards women, of whom there are six (Harrow the Ninth, Dulcinea the Seventh, Abigail the Fifth, Coronabeth and Ianthe the Third, and Judith the Second) opposite three men (Isaac the Fourth, Palamedes the Sixth, and Silas the Eighth); however, this is offset by the First priests, consisting of two men and one non-binary. This leaves the total at 10 women, 9 men, and 1 enby.
    • This also applies to secondary characters from the Ninth House; there are three notable women there (Aiglamene, Glaurica, and the actually-long-dead Pelleamena), and three notable men (Crux, Ortus, and the also-long-dead Priamhark).
  • Genre-Busting: Gideon the Ninth blends a lot of different styles, from magic and spaceships, murder mysteries, thrillers, coming of age, and even some romance elements, to the point where even published reviews often comment on how many genres it crosses.
  • The Good, the Bad, and the Evil: Especially stands out in the final battle. Naturally, our protagonists are the Good. Ianthe, a largely selfish character who unabashedly murdered her cavalier to become a Lyctor, is the Bad, and teams up with the Good to fight the Evil: Cytherea, who intends to murder everyone at Canaan House in a revenge plot against the Emperor.
  • Hands-On Approach: Gideon gets up close and personal to Harrow to teach her how to grip her longsword. Except this is after Gideon's dead and Harrow's absorbed her soul, making this possibly the most heartbreaking and metaphysical use of this trope ever.
  • Happily Married: Abigail Pent and Magnus Quinn of the Fifth House have been married for over a decade, and are the most well-adjusted duo of the entire cast. Naturally, they're the first to die.
  • Hated Hometown: Gideon feels nothing but resentment for the Ninth House, is beyond delighted to leave it behind, and loves the idea of the whole place just dying and disappearing. Character Development eventually has her letting her hatred go, and it's a major sign of growth that her last words are "For the Ninth!"
  • Haunted Castle: Canaan House, at least according to Teacher.
  • Held Gaze: Gideon and Harrowhark do this a lot.
  • The Hero Dies: Act 4 ends with Gideon herself committing a Heroic Suicide so Harrow can become a Lyctor and stop Cytherea.
  • Hero Killer: Invoked by Cytherea, who plans to take revenge on the Emperor by killing all the heirs and cavaliers at Canaan House to deprive him of new potential Lyctors for his army. And while she doesn't succeed in this entirely, she does manage to directly kill six of the heroes—Protesilaus and Dulcinea the Seventh, Magnus and Abigail the Fifth, and Isaac and Jeannemary the Fourth—and causes the deaths of two more, Palamedes and Gideon, who are forced into Heroic Suicides to try to stop her. The paranoia caused by her murders also directly leads to Marta's death.
  • Heroic Suicide: Gideon skewers herself in the heart so Harrow can extract her soul and become a Lyctor powerful enough to kill Cytherea to save both Harrow and Camilla.
  • Heroes Prefer Swords: All the cavaliers have swords, technically, but Gideon has a special enthusiasm for them and is the only one to favor a longsword (a Zweihander, specifically) instead of a rapier.
  • Hidden in Plain Sight: The secret of Lyctorhood is not just hinted at, but indirectly stated very early on, but is not explicitly commented on until Ianthe asks why there were sixteen acolytes and then only eight Lyctors. As early as the very first summons from the Emperor, the First often refers to necromancers being "joined" with their cavaliers as they ascend to Lyctorhood.
  • Impaled with Extreme Prejudice: Isaac and Jeannemary both die impaled by dozens of bones. The last we see Judith, she has one pierced in her gut, and Palamedes says there's nothing that can be done for her. It's also how Gideon kills herself so Harrow can extract her soul and ascend to Lyctorhood.
  • Impersonation-Exclusive Character: Since the real Dulcinea Septimus was Dead All Along, having been Killed Offscreen and replaced before the Seventh's shuttle even reached the First, none of the other characters at Canaan House have ever met her (in person, at least, since Palamedes and Camilla were Pen Pals with her). Throughout the entirety of the book, all interactions they have with "Dulcinea" are really with her imposter, Cytherea.
  • In-Series Nickname:
    • Harrow usually calls Gideon "Griddle," to the point that Gideon is surprised and delighted on the very rare occasions she uses her proper first name.
    • Coronabeth and Ianthe use the nickname "Babs" for their cav Naberius.
  • Insulted Awake: Palamedes calls himself the greatest necromancer of his generation, offending Harrow enough that she surfaces from her blackout for a few seconds just to refute him.
    Palamedes: Thought that would wake her up.
  • Kill and Replace: One of the biggest twists of the book is that the murderer of Canaan House did this to Dulcinea Septimus before ever arriving there. The "Dulcinea" that the characters and audience meet is really Cytherea the First, who intends to murder all of the other necromancers and cavaliers to prevent the Emperor from gaining any more Lyctors for his army.
  • Killed Offscreen:
    • Many of the dead are found just after they've been killed, starting with the Fifth, and extending to Marta and Naberius, but the most dramatic being Jeannemary, who is killed while Gideon is in the same room as her while they're both sleeping.
    • Protesilaus and the real Dulcinea are revealed to be Dead All Along, with Cytherea having invaded their shuttle and murdered them before they ever arrived on the First.
    • Gideon discovers from Silas that Ortus and Glaurica, who stole her escape shuttle near the beginning of the book to flee to the Eighth after the Emperor's summons, were killed when the ship exploded on the way. She talks to Harrow about it and learns that Crux was responsible for planting a bomb onboard.
  • Lame Pun Reaction: Nobody but Coronabeth reacts to Gideon and Magnus's puns with anything but disgust.
  • Like Brother and Sister: Several of the House necromancer and cavalier pairs have this dynamic, most especially the Third, Fourth, and Sixth, though Camilla is heavily implied to have a crush on Palamedes.
  • Love Dodecahedron: Camilla is strongly hinted to have feelings for her necro, Palamedes, who greatly cares for her, but apparently only platonically. He's been in love with Dulcinea for years, who may or may not have loved him back (though the narration leans more towards her having seen them as Just Friends), but at least turned down his marriage proposal. At the Lyctor trials, she seems to be interested in Gideon, who definitely has a crush on her too and is unaware of Palamedes's relationship with her until near the end. However, Gideon is also attracted to Coronabeth, and gradually falls for Harrow over the course of the book as they mend their relationship. This is mutual, as Harrow also seems to be falling for Gideon and is hinted to be jealous of the time she spends with Dulcinea, but she's also been enamored with the girl in the Locked Tomb since first seeing her at age ten. And then we find out that "Dulcinea" was actually Cytherea all along, though her Villainous Crush on Gideon was apparently genuine.
  • Man of Kryptonite: When the bone golem shows up and starts killing people, Gideon repeatedly says she wishes Harrow was around, since she'd see it as little more than a fun puzzle to be dismantled. When it does appear before Harrow, bigger and more terrible than ever before, she acts exactly like Gideon thought, and just orders Gideon to distract it for a moment. Gideon calls her its natural predator.
    Harrow: Nav, show them what the Ninth House does.
    Gideon: We do bones, motherfucker.
  • Many Spirits Inside of One:
    • It's revealed that Teacher is in fact a thousand souls stuffed into one corpse, the result of some horrific Canaan House experiment.
    • This also happens briefly to Colum, as a number of malignant forces possess his unoccupied body while Silas was siphoning from him, leading to some very disturbing Body Horror and both Silas's and Colum's deaths.
  • Meaningful Name: In fact, the book even features an appendix where the author discusses how she chose the characters' names, in many cases based on their personalities or roles in the story; a memorable example is Dulcinea, who, as a reference to Don Quixote, is someone who "you really want to exist, but who really doesn't". Meanwhile, everyone's last name is a reference to the number of their House in some language. For instance, Nav is Breton for 'nine', Ebdoma is Greek for 'seventh', Sextus is Latin for 'sixth', and Chatur is Sanskrit for 'four'.
    • Nav additionally refers to the "souls of the dead" in Slavic folklore, and can be translated to "corpse" in some Slavic languages.
  • Men Are the Expendable Gender: Downplayed, but present, considering that the cast starts out with an almost-perfect gender-equal ensemble.
    • By the end of the book, the only two named male characters still alive are guys who played a fairly minor role in this book: Crux (who hasn't been seen since Act 1) and the Emperor (who only briefly shows up in the epilogue). Both major characters still alive are women (Harrow and Ianthe), plus the minor female character Aiglamene (also not seen since Act 1), and three more women's statuses are unknown but are later confirmed to be alive (Camilla, Coronabeth, and Judith).
    • It's especially noticeable in the final battle. Right before it begins, the final male character still alive at Canaan House, Palamedes, blows himself up in an attempt to stop Cytherea from killing everyone else. By the time the fighting starts, all the characters still alive to participate in it are women.
  • Merger of Souls: It turns out that a necromancer becomes a lyctor by killing their cavalier and absorbing the cavalier's soul into their own, leading them to acquire skills like sword fighting that the cavalier had.
  • Mind Meld: The first Lyctor challenge Harrow and Gideon undertake involves this. Harrow also uses this ability to access Palamedes's photographic memory of a key he wants Harrow to recreate.
  • Mugging the Monster: When the Second makes a push to confiscate everyone's keys as a self-righteous attempt to "protect" them and stop any more lives from being lost, Judith issues the challenge to the Sixth—a House known for being Non-Action Guys—because she thinks it'll be an easy win for her cavalier and hopes to use the victory to persuade the other Houses to fall in line. Instead, Camilla the Sixth solidly defeats Marta the Second, and Palamedes directly calls Judith out on being a bully when he takes her key from her.
  • Muscles Are Meaningful: Cavaliers are all very fit and muscular—Jeannemary is jealous of Gideon's biceps. In fact, it turns out that the tradition of cavaliers using rapiers is because they need to use a blade that the generally less-fit necros can handle. When Ianthe absorbs Naberius, despite getting his fighting skill, she quickly has to switch back to necromancy while fighting Colum, who's twice her size, because she's not muscular enough to handle fighting with a sword for long periods (though Naberius actively struggling against her certainly isn't helping). It even extends to Lyctors, as despite a myriad of experience, Cytherea too has to rely on necromancy to avoid being physically overpowered by Camilla and Gideon. And although Gideon is able to help Harrow use her two-hander immediately after they merge, she says that Harrow's going to need to seriously lift some weights.
  • Mutual Kill: Between Marta and Teacher after the Second attempts to contact the Cohort for backup and the latter attempts to stop them. This also causes the deaths of the other two First priests, whose lives seem to be connected to his.
  • Mysterious Note: The Lyctoral labs are full of them, largely untidied scraps from the original Lyctors and their cavaliers. Most are mundane, but Gideon finds a partial scrap of a note in the Second's Lyctoral study in which her name is mentioned, a fact which alarms her greatly but that she doesn't find time to address. It's not explained until the next book in the series.
  • Never Found the Body: Gideon's Heroic Suicide leaves her corpse resting out in the open, but it's not found when the Emperor's forces arrive at Canaan House.
  • Never One Murder: Abigail and Magnus are found dead at the end of Act 2, but they're far from the last to die. Protesilaus goes missing not long after, and it all escalates from there.
  • Not the First Victim: The investigation into two murders in the Closed Circle of the Lyctoral Trials is complicated when they find two burnt bodies who were killed before their arrival. One turns out to be an entrant whose identity the murderer stole.
  • Not What I Signed on For: All the necromancers have answered the Emperor's summons to potentially become Lyctors, which they regard as a signal honor. Of the four necromancers who survive long enough to figure out what this process entails, only Ianthe willingly does so. Palamedes and Silas reject the entire concept (the former on morals, the latter as blasphemous), and Harrow ends up not having a choice and tries to undo it afterwards.
  • Of Corpse He's Alive:
    • Hilariously, Harrow has gotten away with doing this with her dead parents for seven years, telling people her parents have taken vows of silence and fasting, among other things.
    • A more serious version occurs with Protesilaus, the very boring Seventh cav who turns out to be a corpse perfectly preserved and puppetted by necromantic forces. Harrow is one of the only people to pick up on it right away, having had experience with her parents.
  • Only Friend: Harrow drops this exact wording in reference to Gideon during their Signature Scene in the pool.
  • Parental Substitute:
    • The Fifth House pair Abigail and Magnus seem to be this for the Fourth House kids Isaac and Jeannemary.
    • Gideon's tough old mentor Aiglamene, who taught her swordplay, is the closest thing Gideon has ever had to a parental figure.
  • Pen Pals: Palamedes Sextus and Dulcinea Septimus, for twelve years before the events of the book. They never met in person before the Lyctor trials, but he even proposed marriage to her at one point.
  • Powered by a Forsaken Child: All but one of the Ninth House's children died when Gideon was an infant. It was blamed on a flu in the monastery's ventilation system, but it was actually nerve gas deliberately deployed by Harrow's parents as part of a ritual to ensure they would conceive a powerful necromancer.
  • The Promise: Harrow asks Gideon to promise her that if Harrow dies, Gideon will return to the Ninth and protect the Locked Tomb in her stead. In the end, Gideon refuses to honor that promise because she won't let Harrow be the one who dies.
  • Pungeon Master: Gideon and Magnus. Gideon even says she assumes puns are automatically funny.
  • Really 700 Years Old: "Dulcinea," who is actually Cytherea the First, one of the Emperor's first Lyctors and over 10,000 years old. Also true of Teacher.
  • Rewatch Bonus: Because there are a lot of revelations at the end of Act 4 that are well foreshadowed in advance, there are a lot of details that fit better into the story once all the mysteries are revealed, particular with regards to Cytherea's Double Meaning-laden conversations throughout the book, almost all of which are cast in a very different light knowing that she is a Lyctor impersonating Dulcinea.
  • Running Gag: Several characters run through multiple synonyms to sarcastically make a point to someone throughout the book. Gideon's take on it, in the form of addressing Harrow as "my [creepy adjective] [leader/witchy noun]" note  also crops up several times.
  • Sacrificial Lion / Too Good for This Sinful Earth:
    • Magnus and Abigail are the kindest and most mature adults of the entire group, serving as the Team Dad and Team Mom. Magnus is also the first person to attempt to befriend a deeply lonely Gideon. So of course, they're the first to die.
    • After Isaac and Jeannemary spend much of the early days at Canaan House too shy and nervous to talk to Gideon—or to anyone else besides the Fifth, really—they start to get some Character Development in Act 3 and gradually join in on the alliance between the Ninth and the Sixth. The two of them, in quick succession, become the next murder victims at the end of Act 3, both dying right in front of Gideon, to boot.
  • Safely Secluded Science Center: The God-Emperor summons Necromancers from the Nine Houses to a palatial laboratory complex on his own planet, which he abandoned and sequestered nine thousand years prior, to challenge them to rediscover the process by which his first servants were transformed into immortal Lyctors.
  • Screw the Rules, I Make Them!: When Judith argues that imperial law still applies at Canaan House, Teacher points out that imperial law is derived from the Emperor, who set their directions personally.
  • Self-Made Orphan: Gideon tells us early on that Harrow killed her own parents, but we find out later on that it was more complicated than that.
  • Shoo Out the Clowns: The largely comedic Fifth are killed off at the end of Act 2, which is the first time the story truly begins to become serious; when the Fourth are also killed at the end of Act 3, the comedy becomes far more downplayed with their deaths and Gideon's ensuing Survivor's Guilt.
  • Sophisticated as Hell: Gideon's entire narrative style, as well as her dialogue.
  • Spotting the Thread:
    • A rare subversion. Cytherea makes several slip ups in her Dead Person Impersonation of Dulcinea, including knowing how Gideon fights (which "Dulcinea" had never seen) and calling Protesilaus's death an accident, when Harrow knows he was stabbed through the heart. However, these moments go unremarked on by the protagonists, and Cytherea is not revealed until the final chapters, after her plan has largely succeeded.
    • Dulcinea guesses that Gideon isn't really a cavalier by deducing that she's used to a heavier sword than a rapier. It goes from a guess to a full-on deduction when Gideon doesn't recognise the phrase "one flesh, one end", which a cavalier and their necromancer would say to each other when the cavalier officially accepts the role.
  • Survivor's Guilt: As the bodies begin to pile up at Canaan House, several characters are left grappling with their survival when others have died. Most especially Gideon after Jeannemary died when Gideon tried to protect her, questioning why she was spared as Jeannemary was nailed to a bed while Gideon slept, but Judith after Marta's death and Harrow's grief after Gideon's death are both partially due to this as well.
  • Technicolor Blade: Some of the cavaliers have rapier blades that match the colors associated with their House, but this is entirely an aesthetic sensibility.
  • Teeth-Clenched Teamwork: Gideon and Harrow have hated each other for their entire lives, so being forced to work together starts out as this, with Gideon only coming with Harrow to Canaan House for a chance to leave the Ninth forever after the Lyctoral trials are complete and never have to see her again. This changes after the deaths of the Fifth, though it takes some time for them to fully set aside the animosity between them.
  • There Are No Rules: Teacher tells the necromancers and cavaliers that the one rule in the Lyctoral challenge is "never open a locked door unless you have permission". A few murders in, he clarifies that that's the only rule — all other laws are suspended for the challengers by the Emperor's divine fiat.
  • Treasure Chest Cavity: How do you hide something from post-cognitives, necromancers and mediums? You hide it inside the body of a murder victim, after she's been examined. Cytherea hid one of the challenge keys needed to unlock a door within Abigail's torso after killing her, planning on waiting until after everyone had examined her to retrive it. It was almost a foolproof strategy, but Ianthe, who had been keeping track of the number of keys in secret, deduced it must have been hidden there and took it for herself. That hiding it inside of Abigail also erased the psychometric finger print that would have pinned her as the killer was a bonus.
  • Uncertain Doom: Although Camilla, Judith, and Corona are still alive when they're last seen by Gideon's narration, the former two also being heavily wounded and incapacitated, they're nowhere to be found when the Emperor's forces search Canaan House.
  • Undead Abomination: The bone construct that Cytherea uses to kill Isaac and Jeannemary, as well as fight the survivors at the end, is massive and inhuman, can shoot bone spikes as projectiles, and can get into places that it by all rights shouldn't be able to.
  • Underestimating Badassery: The three Houses expected to bring the worst cavaliers to Canaan House based on the reputation alone are the librarian Sixth, the siphoning Eighth, and the decrepit Ninth. Guess who three of the best cavaliers at Canaan House are?
    • Gideon quickly demonstrates early on in duels with Magnus the Fifth and Naberius the Third that she is an exceptional cavalier, and the rest of the Houses remain too intimidated to duel the Ninth for the remainder of the book.
    • Judith Deuteros the Second instead challenges the Sixth House to a duel to make an example of them, and everyone thinks they're about to see a soldier beat up a librarian. Everyone except Gideon, who's fought Camilla, and who can barely suppress her grin. Camilla the Sixth swiftly proves her House is not to be underestimated.
  • Unseen Pen Pal: Palamedes and Dulcinea became close friends over twelve years of letter-writing, but live on different planets and meet in person for the first time when they join the Lyctoral trials. This causes him to miss that she was killed and replaced by Cytherea just before the trip.
  • Wham Line: Gideon the Ninth has quite a few as the reveals pile up in the final act, but there are two particularly big ones:
    • Gideon and Harrow finally reconciling leads to Harrow revealing the darkest secret of the Ninth, one that explains why Gideon grew up hated by her entire House:
      "Why leave me though?" [Gideon] demanded. "They murdered the rest of the House, but left me off the list?"
      There was a pause.
      "We didn't," said Harrow.
    • And then, the line from Camilla that indirectly reveals that a major character has been lying, and serves as Five-Second Foreshadowing for who the murderer is:
      Camilla: The Warden has been exchanging letters with Dulcinea Septimus for 12 years.(...) One of the reasons he became heir of the House was to meet her on even footing. His pursuit of medical science was entirely for her benefit.
  • World of Action Girls: Nearly every female character in the book qualifies as an Action Girl.
    • This, naturally, includes all four of the female cavaliers; Gideon and Camilla are two of the very best fighters at Canaan House, Marta is a skilled and very experienced soldier, and while we don't see her fight much, Jeannemary is implied to be a Little Miss Badass and Child Prodigy.
    • Though they're not so much physical fighters, the necromancers are no slouches either. Harrow is a standout, being able to best Gideon in their fight at the beginning and more than holding her own in the final fight; meanwhile, though we don't see Judith actually perform much necromancy, she's a skilled and decorated soldier like Marta with years of experience. And then we have Dark Action Girl Lyctors Ianthe and Cytherea, who take it to a whole different level.
    • The only exceptions that we see are Team Mom Abigail (who's given no spoken or seen indication that she's a fighter), the sick Dulcinea (understandably), and Coronabeth (who at least knows a lot about duels, but doesn't seem to be much of a dueler herself).
  • You Called Me "X"; It Must Be Serious: Both times Harrow actually calls Gideon by her first name instead of "Griddle" or Nav, Gideon calls her out on it. The first time happens when she's scared Gideon is about to die, and the second occurs when she asks Gideon to make her an important promise after a heart-to-heart.