Gideon the Ninth by Tamsyn Muir is the dark space fantasy I didn’t know I needed. In a galaxy with nine ancient houses with nine rulers and heirs adept in different forms of necromancy, the Emperor needs necromancers. Each necromancer has their swordsman, their loyal cavalier primary, except the ninth. Gideon, an orphan raised by the unfriendly nuns and creepy skeletons of the Ninth House, maybe a swordswoman, but she doesn’t want to be loyal to the necromancer of the Ninth, Harrowhark Nonagesimus. Reluctantly, to win her freedom from the creepy Ninth House, Gideon agrees to serve as Harrow’s cavalier primary as Harrow serves the Emperor.

In the first book in The Locked Tomb series, the nine houses gather to take part in a series of trials meant to determine who will be the next lyctor, which would make a person more powerful than a necromancer and more closely connected to the Emperor. Gideon is tasked with helping Harrow win these trials and become lyctor, which will keep the Ninth House from falling and gain Gideon her freedom. With Harrow’s skill in necromancy and Gideon’s skill with a sword, this should be easy, except the two girls hate each other, and have spent the past ten years as practically the only children in their House, hating each other the whole time. Undisciplined and improper Gideon spends much of her time suspicious and untrusting of calculating and controlled Harrow. Their dynamic is hilarious, frustrating, and addicting.

The first in The Locked Tomb series, Gideon the Ninth was an incredibly atmospheric, intricately plotted genre-defying space fantasy with significant horror and romance elements, and a lot of humor too. The lore is expansive, but easy to fall into, especially thanks to the characters, who are weird and charming and fascinating. The end felt like a suckerpunch, while also feeling extremely true to the rest of the book, and left me very excited to read the second in the series, Harrow the Ninth.