Harrow the Ninth, the sequel to Gideon the Ninth, turns a galaxy inside out as one necromancer struggles to survive the wreckage of herself aboard the Emperor's haunted space station. She answered the Emperor's call. She arrived with her arts, her wits, and her only friend. In victory, her world has turned to ash. After rocking the cosmos with her deathly debut, Tamsyn Muir continues the story of the penumbral Ninth House in Harrow the Ninth, a mind-twisting puzzle box of mystery, murder, magic, and mayhem. Nothing is as it seems in the halls of the Emperor, and the fate of the galaxy rests on one woman's shoulders. Harrowhark Nonagesimus, last necromancer of the Ninth House, has been drafted by her Emperor to fight an unwinnable war. Side-by-side with a detested rival, Harrow must perfect her skills and become an angel of undeath — but her health is failing, her sword makes her nauseous, and even her mind is threatening to betray her. Sealed in the gothic gloom of the Emperor's Mithraeum with three unfriendly teachers, hunted by the mad ghost of a murdered planet, Harrow must confront two unwelcome questions: is somebody trying to kill her? And if they succeeded, would the universe be better off?

The Emperor needs necromancers. The Ninth Necromancer needs a swordswoman. Gideon has a sword, some dirty magazines, and no more time for undead bullshit. Brought up by unfriendly, ossifying nuns, ancient retainers, and countless skeletons, Gideon is ready to abandon a life of servitude and an afterlife as a reanimated corpse. She packs up her sword, her shoes, and her dirty magazines, and prepares to launch her daring escape. But her childhood nemesis won't set her free without a service. Harrowhark Nonagesimus, Reverend Daughter of the Ninth House and bone witch extraordinaire, has been summoned into action. The Emperor has invited the heirs to each of his loyal Houses to a deadly trial of wits and skill. If Harrowhark succeeds she will become an immortal, all-powerful servant of the Resurrection, but no necromancer can ascend without their cavalier. Without Gideon's sword, Harrow will fail, and the Ninth House will die. Of course, some things are better left dead.