Gideon the Ninth
Locked Tomb book #1. Published 10 September 2019.
Gideon Nav has spent her entire adolescence yearning to leave the dreary Ninth House. Being "raised" by decrepit nuns and antagonistic retainers would make anyone ready to run off and join the Empire's military. With her sword in hand she prepares to join the Cohort battling in space, but there's one catch to leaving the planet for good. The Reverend Daughter of the Ninth House, Gideon's boss and enemy, forbids her to leave—without her.
The Emperor has called for the necromancy practicing heirs from each of his Nine Houses to gather and try their hand at discovering the secret to immortality. Harrowhark, necromantic prodigy and heir to the Ninth, sees this as her chance to restore her House from the brink of extinction. But she needs a competent fighter to act as her required cavalier.
And so Gideon is coerced to serve the head of the Ninth House in a way she never has before. As the cavalier protecting Harrow from the dangers of the Emperor's Lyctor trials.
The pair travel to another planet where a gothic mansion stands alone in the middle of an ocean. The locked rooms, that are forbidden to be opened by anything other than their designated keys, hold more secrets than anyone bargained for. In a race for survival neither the house nor the other Houses play nice.