Book profile

Gideon the Ninth

The Locked Tomb #1

by Tamsyn Muir

Science fantasyGothic fantasyFantasy mystery
Compare this book
First published
2019
Audience
Adult
Series position
1 of 3
Series status
Ongoing series
Commitment
Medium series
Profile basis
Individual book

Taste profile

At a glance

How the matrix works
Tone
Gothic
Pace
Fast
Magic
High
Prose
Moderate
Romance
Major thread

A sword-wielding prisoner accompanies her necromancer rival to a lethal trial in a decaying space palace.

The relationship between Gideon and Harrow is a major emotional thread, but the book does not deliver a conventional romantic arc. Readers matching on romance role still need the body text to understand that distinction.

Best if you want

  • Gothic necromancy, dark humor, swordplay, and a difficult central bond.
  • A dense science-fantasy mystery designed to reward rereading.

Think twice if you need

  • A completed series or straightforward explanations.
  • Low horror, restrained language, or conventional romance delivery.

Fantasy Fit Matrix

Gideon the Ninth

Individual book / gothic tone / fast pace

Taste intensity

Political intrigue

4/ 5

Darkness

4/ 5

Character focus

5/ 5

Plot complexity

5/ 5

Worldbuilding depth

5/ 5

Taste categories

Prose difficulty
ModerateAccessible / Moderate / Literary
Romance role
Major threadNone / Subplot / Major thread / Central
Magic presence
HighLow / Medium / High
Magic-system type
HybridNone / Soft / Hard / Hybrid

Reading commitment

Series status
Ongoing series
Series commitment
Medium series
3 published books

Outside the score

Reader context

Audience and content guidance help prevent unsuitable matches. They do not change what a Matrix value means.

Intended audience
Adult
Profile basis
Individual book
The Matrix values describe this volume, not an average for the whole series.
Series context
The Locked Tomb
Volume 1 of 3 published books.

Reader advisories

  • Violence
  • Strong language
  • Horror elements
  • Grief and loss

This is practical guidance, not an exhaustive content-warning list.

How the series changes

Each volume changes narrator and structure while revealing more of the empire's history and central relationships.

Plot complexity
StartsA lethal trial in one palaceLaterA nonlinear imperial and planetary conflict
Prose difficulty
StartsModerate but slang-heavyLaterStructurally and referentially demanding

Data quality

Editorial record

Matrix v1.0 / calibrated / high confidence / reviewed 2026-08-06

If you liked Gideon the Ninth, start here.

The closest matches in the current library, calculated with Matrix v1.0. Scores reflect taste similarity and audience suitability. Books from this series are excluded, and each recommended series appears only once.

79.3%

Calculated fit

Complete series

Red Sister

by Mark Lawrence / Book of the Ancestor

Best if you want
A dark female-led academy story with fast combat and strong friendships.
Think twice if you need
Low violence, safe schooling, or romance as a major thread.
Closest match
The strongest alignment is in character focus and worldbuilding depth.
Biggest difference
The clearest shift is in subgenre and tone.

78.4%

Calculated fit

Complete series

Six of Crows

by Leigh Bardugo / Six of Crows

Best if you want
A fast fantasy heist with intricate plans and reversals.
Think twice if you need
Older protagonists or a slow introduction to the wider world.
Closest match
The strongest alignment is in character focus and political intrigue.
Biggest difference
The clearest shift is in subgenre and magic presence.

77.6%

Calculated fit

Standalone

Jonathan Strange & Mr Norrell

by Susanna Clarke

Best if you want
A complete, deeply researched historical fantasy with literary prose.
Think twice if you need
A fast opening, short chapters, or a compact book.
Closest match
The strongest alignment is in worldbuilding depth and political intrigue.
Biggest difference
The clearest shift is in pace and subgenre.

76.2%

Calculated fit

Complete series

Harry Potter and the Deathly Hallows

by J. K. Rowling / Harry Potter

Best if you want
A darker payoff to a long coming-of-age arc.
Think twice if you need
A standalone entry point.
Closest match
The strongest alignment is in worldbuilding depth and political intrigue.
Biggest difference
The clearest shift is in subgenre and tone.

75.4%

Calculated fit

Complete series

The Jasmine Throne

by Tasha Suri / The Burning Kingdoms

Best if you want
Dense political fantasy led by women with a major sapphic romance.
Think twice if you need
Simple factions, low darkness, or a quickly explained world.
Closest match
The strongest alignment is in character focus and worldbuilding depth.
Biggest difference
The clearest shift is in tone and subgenre.