Harrow’s eyes flickered open. “Stop.”

“I am your sworn sword, night boss.”

“Fine,” said Harrow heavily.

Gideon’s mouth was about to round out the words “bone empress” before she realised what had been said. The expression on the other girl’s face was now all resignation: resignation and exhaustion and also something else, but mostly resignation. “I acknowledge your argument,” she said. “I disagree with it, but I see the margin of error. Fine.”

It would have been pushing her luck to point out that there was no real way Harrowhark could have denied her; she had the key, the upper hand, and significantly more blood. So all she said was, “Okay. Great. Fine.”

“And you had better stop it with all this twilit princess garbage,” said Harrow, “because I may start to enjoy it. Helping me will be achingly dull, Nav. I need patience. I need obedience. I need to know that you are going to act as though giving me devotion is your new favourite pastime, even though it galls us both senseless.”

Gideon, dizzy with success, crossed one leg around the other and leant back on the dresser in a posture of triumph. “Come on. How bad could it be?”

Harrow’s lips curled. They showed her teeth, stained slightly pink with blood. She smiled again—slower than before, just as terrible, just as strange.

“Down there resides the sum of all necromantic transgression,” she said, in the singsong way of a child repeating a poem. “The unperceivable howl of ten thousand million unfed ghosts who will hear each echoed footstep as defilement. They would not even be satisfied if they tore you apart. The space beyond that door is profoundly haunted in ways I cannot say, and by means you won’t understand; and you may die by violence, or you may simply lose your soul.”

Gideon rolled her eyes so hard that she felt in danger of twisting the optic nerve.

“Knock it off. We’re not in chapel now.”

But Harrow said: “It’s not one of mine, Griddle. I’m repeating exactly—to the word—what Teacher said to me.”

“Teacher said that the facility was chocka with ghosts and you might die?”

“Correct.”

“Surprise, my tenebrous overlord!” said Gideon. “Ghosts and you might die is my middle name.”

14

THIS LAPSE OF HARROWHARK’S did not make her one bit nicer to live with. Very early next morning, despite all logic and sense, she forced Gideon to put on the robe and paint on the paint like every morning since they’d arrived at Canaan House: she was impatient with what Gideon saw as the necessities of life, i.e., eating breakfast and stealing lunch. Gideon won the breakfast argument, but lost the right not to stare wretchedly at the mirror as she stippled black paint over her cheekbones.

At Harrow’s behest, the Ninth House moved through the silent grey corridors like spies. There were many times when the necromancer would stop in the shadow of a doorway and wait there for fully five minutes before she would allow them both to carry on, to creep noiselessly down the shabby staircases and down to the bowels of the First. They only met one person on the way: in the light before sunrise, Harrow and Gideon pressed themselves up into the shadow of an archway and watched a figure with a book clenched in one hand cross a dusty hall, silent and shadowed, littered with sagging chairs. Because she had spent her whole life in the darkest hole of the darkest planet in the darkest part of the system, Gideon could make out the etiolated profile of the repellent Third twin, Ianthe. She disappeared out of sight and Harrow remained, silently waiting, far longer than Gideon thought necessary before she gestured for them to move.

They made it to the dismal hole with the access hatch without incident, though it was dark enough there that Gideon had to pocket her glasses and Harrow had to tug down her veil. Harrow was breathing impatiently through her nose as Gideon slid the key into the lock, and flung herself down the hole as though being chased. They descended the long, frigid ladder, and Harrow brushed herself off at the bottom.

“Good,” was the first thing she said since they’d left the room. “I’m relatively sure we’re alone. Follow me.”

Dogging her adept’s rapid steps, rapier bumping against her hip, Gideon was interested to see that they did not traverse the mazelike corridors to Sanitiser. They instead passed down a long, broad hallway, buzzing quietly with the sound of electric light, until after a few corners they reached a door marked LABORATORY TWO. Harrow pushed this open.

The little foyer beyond was cupboard sized. There were hooks on the walls, and on one what Gideon took to be some ugly, partly dissolved tapestry, until she realised it was the remains of somebody’s abandoned coat. On the door ahead was a dilapidated folder behind a piece of plex, with a scribbled and pale title in a faded, haphazard hand: #1–2. TRANSFERENCE/WINNOWING. DATACENTER.

Above the sterile metal door was the more familiar sight of a mounted skull, probably once painted red but now tarry brown. It had lost its jaw at some point and seemed all front teeth. Harrow fussily crammed minuscule chips of phalange in and around the entryway. It was an unusual experience to be crossing, rather than barred from, a Nonagesimus bone ward, but Gideon didn’t get the time to enjoy it: Harrow pushed through the door and led Gideon through to another room.

This room—more spacious, more elongated—gave the distinct impression of having been ransacked. It was ringed with broad metal desks, and the walls were pockmarked with empty electrical sockets. There were shelves and shelves that must once have contained books and files and folders, but now only contained a lot of dust; there were discoloured places on the walls where things must have been tacked up and had since been taken down. It was a naked and empty room. One wall was windowed all along its length to let you see into the chamber ahead, and that wall had a door in it marked with two things: one, a sign on the front saying RESPONSE, and two, a little plaque on the top marked OCCUPIED. This had a bleary glow of a green light next to it, indicating that Response was probably not occupied. Looking through to Response—a bleak, featureless chamber, characterised only by a couple of vents on the far side of the square—the floor was an absolute shitshow of bits of broken bone.

The other wall—filled with brackets to prop up books that had long since been removed—had a door too, and this one was labelled: IMAGING. The Imaging door had the same plaque as Response, but with a little red light instead. Imaging also had a little plex window whose outside was smeared with old bloody handprints.

“Someone’s been having fun in here,” said Gideon.

Harrow shot her a look but did not enforce the vow of silence. “Yes,” she said. “Me.”

Her cavalier tried the door marked Response, but it wouldn’t move and there didn’t seem to be a conventional touchpad. Harrow said, “It won’t open like that, Nav. Come with me, and don’t touch anything.”

Gideon went with Harrow and did not touch anything. The autodoor to Imaging obligingly opened at their approach, revealing a dismal cupboard of a room with a huge array of old mechanical equipment, lightless and dead. A single ceiling panel fuzzed its way to life, white and pallid and not revealing much but more shadow. The long desk still had what she realised was a rusted old clipboard, to which a thin, nearly transparent piece of paper was attached. Gideon at last gave in to the urge to touch something, and the paper dissolved as though it were ash. It left a grey stain on her fingertips.